Mr Darwin’s Fishes.

Mr. Darwin’s Fishes was displayed in the Jenyns room in 2009 as part of BRLSI’s very successful Darwin and Beyond programme, celebrating the 150th anniversary of the publication of On the Origin of Species (24 November 1859) and the 200th anniversary of Darwin’s birth (12 February 1809). Leonard Jenyns, who later in his life settled in Bath and was intimately connected with BRLSI, was invited to undertake the voyage aboard HMS Beagle prior to Charles Darwin. Jenyns reluctantly refused the opportunity and the rest is history! Darwin collected numerous fish specimens on his voyage aboard HMS Beagle and on his return they were described by his lifelong friend, Jenyns.

Leonard Jenyns

Clergyman and naturalist

Jenyns was a country vicar and a keen, methodical recorder of natural history and meteorology when he and Darwin first met in 1828. Like Darwin, he had studied at Cambridge, but a few years previously. Since then he had taken on a rural parish a few miles beyond the city. Darwin at first did not have a high opinion of him, but their mutual interest in beetle collecting cemented their friendship.

Jenyns was typical of many Victorian clergymen who found the time to take up natural history with great devotion, believing that the great diversity of nature revealed the wonder of God. His particular preoccupation was his large collection of Cambridgeshire insects and fresh water molluscs. It was to Jenyns that Darwin appealed when he returned from his voyage on the Beagle and needed his specimens of fish studied for publication. Jenyns took four years to complete this and found it a demanding task.

“Regard for my old friend, and the interest I took in all the valuable results of his celebrated voyage, induced me to comply. But the work cost me a great deal of labour…..” Jenyns wrote in his autobiography ‘Chapters in My Life’.

This exhibition shows how the different roles of the collector of the fish, Darwin, and their cataloguer, Jenyns, combined in the publication of ‘The Fishes of the Voyage of the Beagle’ and looks at the way these two distinct personalities approached their work.

Charles Darwin

A Curious Mind

Darwin arrived in Cambridge aged 18 to prepare for a career in the clergy. The life of a country parson like Jenyns was attractive to young gentlemen as it offered time to study natural history and build up collections between parish duties.He had already abandoned a career in medicine after two fruitless years of study in Edinburgh, revolted by the surgical techniques he had to witness and the dull lectures, confident that the family name and fortune would ensure a comfortable future for him.

He enjoyed the conventional pursuits of the young country gentleman, shooting and hunting with ‘some dissipated low-minded young men’. He might have squandered his time at university, but for his friendship with the Professor of Botany, John Stevens Henslow. This brought him into contact with a circle of naturalists and men of science, including Jenyns, and placed him among a network of intellectuals with whom he corresponded for the rest of his life.

John Stevens Henslow

Darwin’s Mentor

At Cambridge Darwin became an ardent disciple of Henslow, the popular Professor of Botany, enrolling for his lectures and joining his field excursions into the Cambridgeshire fenland. At Henslow’s Friday evening soirées, academics and undergraduates mingled informally to show off their latest specimens and talk about natural history.

‘He would receive with interest the most trifling observation on any branch of natural history; and however absurd a blunder one might make, he pointed it out so clearly and kindly, that one left him in no way disheartened, but only determined to be more accurate the next time’. wrote Darwin of Henslow.

Henslow was compiling a herbarium of British flora, organised in a distinct way so that each page compared several plants of the same type from different locations, emphasising variation within species. This unorthodox approach influenced Darwin’s own methods of observation, and served him well later in life as he developed his evolutionary theory. Henslow had married Jenyns’s sister and this family connection bought Jenyns and Darwin together in the pursuit of their common passion—collecting beetles.

Fish from the Beagle

Darwin had a free hand to pursue his studies of natural history and geology and he planned to collect new species where possible. The Beagle was at sea for long periods while the task of surveying took place, so he had ample opportunity both to collect marine animals and study them during those long hours, making notes using his single lens Bancks microscope.

The efficient methods with which he organised his written records, in cramped conditions and often laid low with seasickness, were an important factor in his success as an observer and collector, and owed much to what he had seen of Henslow’s practice and method in the field of botany.

The early entries in the Diary record Darwin’s sense of excitement:
…collected numerous marine animals all of extreme interest. I am frequently in the position of the ass between two bundles of hay; so many beautiful animals do I generally bring home with me.
Beagle Diary, 30 Jan 1831 St Jago

The equipment that he had scurried round to purchase before the Beagle sailed, on the advice of numerous naturalists, gave him much satisfaction:

I proved today the utility of a contrivance which will afford me many hours of amusement and work; it is a bag four feet deep, made of bunting, and attached to a semicircular bow…dragged behind the vessel. This evening it brought up a mass of small animals and tomorrow I look forward to a greater harvest…
And, next day: I am quite tired having worked all day; at the produce of my net. The number of animals…is very great…many are most exquisite in their forms and rich colours. It creates a feeling of wonder that so much beauty should be apparently created for such little purpose.
Beagle Diary, January 10th and 11th, 1832

Some of the type specimens collected by Darwin on the voyage of the Beagle, photographed in the Natural History Museum, London. The colours have now almost entirely faded.

Nuances of colour

Darwin filled four notebooks on board the Beagle to record his field observations. His notes are models of critical study, always questioning the logical implications of his findings, and his attention to the colour of his specimens was ahead of its time.

His descriptions seem at first glance to sparkle with a kind of poetic intensity; in fact he relied on a reference book Werner’s Nomenclature of Colours (in an English edition by Patrick Syme 1821) which contained hand-painted colour swatches with standardised names. By matching a the colour of a specimen with one of Syme’s colours, it was possible to convey a description which could be accurately interpreted away from the field. This would have been useful to Jenyns who found that the spirits of wine used to preserve the fish specimens had faded their colours significantly.

An extract from Patrick Syme’s English version of Werner’s Nomenclature of Colours

An example of Darwin’s use of colour reference taken from Werner’s book is this description of the sea off the coast of Brazil:
I had been struck by the beautiful colour of the sea when seen through the chinks of a straw hat … it was, according to Werner nomenclature, Indigo with a little Azure blue. The sky at the time was Berlin with little Ultra marine blue & there were some cirrocumuli scattered about.
Beagle Diary, March 1832, Bahia, Brazil

This vibrant description by Darwin is of a dogfish, using Symes’ colour names; the specimen did not survive preservation and Jenyns had to discard it later on.

Squalus (dogfish)
Body “blueish grey”; above, with rather blacker tinge; beneath much white:— Its eye was the most beautiful thing I ever saw.— pupil pale “Verdegris green”, but with lustre of a jewel, appearing like a Sapphire or Beryl.— Iris pearly edge dark.— Sclerotica pearly:— In stomach was remains of large fish.
Extract from Fish in Spirits of Wine

The Diodon — observed by Darwin and described by Jenyns

During the five year journey, Darwin was encountered many new organisms in widely differing environments but he had at hand an extensive library of reference books, chiefl y the well known works of French specialists like Cuvier and Lamarck. The bulk of his notes are devoted to geology and marine invertebrates, his real passions, but the notes he made about his encounters with fish are distinguished by their skilful and accurate observations and their vivid descriptions of particular behaviour.

An example is his detailed description of how the extremely poisonous puffer fish, Diodon, can rapidly inflate when threatened by swallowing water or air until almost spherical in shape. Challenging Cuvier’s opinion, he makes his own original and precise analysis.

Below-right: Diodon sp. (image courtesey of Emme Interactive)

Darwin’s original notes

A Diodon was caught swimming in its unexpanded form near to the shore. — Length about an inch: above blackish brown, beneath spotted with yellow. — On head four soft projections: the upper ones longer like the feelers of a snail. Eye with pupil dark blue; iris yellow mottled with black. — The dorsal caudal and anal fi ns are so close together, that they act as one. These as well as the Pectorals, which are placed just before the bronchial apertures, are in a continual state of tremulous motion, even when the animal remains still. — The animal propels its body by using these posterior fi ns, in same manner as a boat is sculled, that is by moving them rapidly from side to side with an oblique surface exposed to the water.— The pectoral fins have great play which is necessary to enable the animal to swim with its back downwards. — When handled a considerable quantity of a fi ne “Carmine red” fi brous secretion was emitted from the abdomen, and stained paper, ivory &c, of a bright colour. — The fi sh has several means of defence it can bite hard, and can squirt water to some distance from its mouth, making at the same time a curious noise with its jaws. — After being taken out of water for a short time, and then placed in again, it absorbed by the mouth (perhaps likewise by the branchial apertures) a considerable quantity of water and air, sufficient to distend its body into a perfect globe. — This process is effected by two methods; the air is swallowed and then forced into the cavity of the body, its return being prevented by a muscular contraction which is externally visible. The water however, I observed entered in a stream through the mouth, which was distended and motionless; hence this latter action must have been caused by the dilatation of the animal, producing suction. When the body is thus distended the papillæ, with which it is covered become stiff, the above mentioned tentacula on the head, being excepted. — The animal being so much buoyed up, the branchial openings are out of water, but a stream regularly fl owed out of them which was as constantly replenished by the mouth. — After having remained in this state for a short time, the air and water would be expelled with considerable force, from the branchial apertures and the mouth. — The animal at its pleasure could emit a certain portion of the water and I think it is clear that the fl uid is taken in partly for the sake of regulating the specifi c gravity of its body. — The skin about the abdomen is much looser than that on the back and in consequence is the most distended; hence the animal swims with its back downwards. — Cuvier doubts their being able to swim when in this position; but they clearly can not only swim forward, but also move round. — this they affect, not like other fish, by the action of their tails, but collapsing the caudal fins they move only by their pectorals. — When placed in fresh water seemed singularly little inconvenienced.

It is a fatal fault to reason whilst observing, though so necessary beforehand and so useful afterwards … Quoted by Emma Darwin as a frequent saying of her husband’s

Jenyns’s report for ‘Fish’

At the same time that Darwin was writing up his notes, Jenyns was also using them for the descriptions of the fish specimens that would become the Fish volume for ‘The Zoology of the Beagle’.

Page 151 vol 4 fish LJ. DIODON ANTENNATUS. Cuv. ?

Diodon antennatus, Cuv. Mém. du Mus. tom. iv. p. 131. pl. 7. A third species of Diodon, brought home by Mr. Darwin, and taken by him at Bahia, in Brazil, is either the young of the D. antennatus of Cuvier, or else
new; but the only individual in the collection is quite small, and not more than an inch in length, excluding caudal. The fl eshy fi laments above the eyes, which, according to Cuvier, so peculiarly distinguish the D. antennatus, are very distinct,— but I see none on the sides. The ground colour would seem darker than he describes, so as to render the spots and markings on the upper parts not distinguishable from it now, if they ever existed. In spirits it appears of a nearly uniform deep brown red. The spines, or rather papillæ, are also shorter than represented in his figure; but this may be only the effect of immaturity. 

According to Mr. Darwin, the colours when recent were as follows: — “Above blackish brown, beneath spotted with yellow. Eye with the pupil dark blue; iris yellow, mottled with black.” It is added: — “On the head four soft projections; the upper ones longer, like the feelers of a snail.” 

Mr. Darwin observes, “that the dorsal, caudal, and anal fins, in this species, are so close together that they act as one: these, as well as the pectorals, are in a continued tremulous motion even when the fi sh is otherwise motionless. The animal propels its body by using the posterior fi ns in the same manner as a boat is sculled, that is, by moving them rapidly from side to side with an oblique surface exposed to the water. The pectoral fi ns have great play, which is necessary to enable the animal to swim with its back downwards.” 

Mr. Darwin made some further observations on the habits of this species, which have already appeared in his “ Journal,” to which I may refer the reader. The tendency of them is to explain the process by which the water and air are absorbed, when the Diodon distends itself into a spherical form; and to show that the fish can swim, when fl oating in this state with its back downwards, which Cuvier doubted. He thinks that the water is taken in partly for the sake of regulating its specific gravity. He also notices a curious circumstance with respect to this species, viz., “ that it emitted from the skin of its belly, when handled, a most beautiful carmine red and fibrous secretion, which permanently stained ivory and paper.”

Tales from the Beagle

The Barred rockfish, (Plectropoma patachonica) Above aureous – coppery; with wave like lines of dark brown, these often collect into 4 or 5 transverse bands, fins leaden colour, beneath obscure; pupil dark blue, when caught vomited up small fish and a Pilumniis. Mr Earle states these fish are plentiful at Tristan da Cunha, where it is called the Devils fish; from the bands being supposed the marks of the Devils fingers. Was tough for eating, but good. Coast of Patagonia.

Notes by Darwin from ‘Fish in Spirits of Wine’ (n.b.  Pilumnus is a kind of hairy crab)

2 April 1832

A flying fish fell on the deck this morning; it struck the mast high up near the main yard: sticking to the fish was a crab, the pain of which caused perhaps this unusual degree of action.

Beagle Diary

7 Jan. 1832

I was much interested, on several occasions, by watching the habits of an Octopus or cuttle-fish. Although common in the pools of water left by the retiring tide, these animals were not easily caught. By means of their long arms and suckers, they could drag their bodies into very narrow crevices; and when thus fixed, it required great force to remove them. At other times they darted tail first, with the rapidity of an arrow, from one side of the pool to the other, at the same instant discolouring the water with a dark chestnut-brown ink. These animals also escape detection by a very extraordinary, chameleon-like, power of changing their colour. They appear to vary the tints, according to the nature of the ground over which they pass: when in deep water, their general shade was brownish purple, but when placed on the land, or in shallow water, this dark tint changed into one of a yellowish green. The colour, examined more carefully, was a French gray, with numerous minute spots of bright yellow: the former of these varied in intensity; the latter entirely disappeared and appeared again by turns. These changes were effected in such a manner, that clouds, varying in tint between a hyacinth red and a chestnut brown, were continually passing over the body. Any part being subjected to a slight shock of galvanism, became almost black: a similar effect, but in a less degree, was produced by scratching the skin with a needle. These clouds, or blushes, as they may be called, when examined under a glass, are described as being produced by the alternate expansions and contractions of minute vesicles, containing variously-coloured fluids.

Darwin, C. R. 1839. ‘Narrative of the surveying voyages of His Majesty’s Ships Adventure and Beagle between the years 1826 and 1836’

Redlip blenny

Fish. Quail island; they bite very severely; having driven teeth through Mr Sullivans finger.

Extract from ‘Fish in Spirits of Wine’, specimen 19

August 28th. Lat 38°S. 25’ South.

Great shark (bad?). Caught by a hook a specimen of genus Squalus; Body ‘blueish grey’; above with rather blacker tinge; beneath much whiter. Its eye was the most beautiful thing I ever saw, pupil pale ‘verdegris green’ but with lustre of a jewel, appearing like a Sapphire or Beryl. Iris pearly edge dark. Sclerotica pearly. In stomach was remains of large fish.

Extract from ‘Fish in Spirits of Wine’, specimen 359

17 September 1835

The Beagle was moved into St Stephen’s harbor. The Bay swarmed with animals; Fish, Shark & Turtles were popping their heads up in all parts. Fishing lines were soon put overboard & great numbers of fine fish 2 & even 3 feet long were caught. This sport makes all hands very merry; loud laughter & the heavy flapping of the fish are heard on every side. After dinner a party went on shore to try to catch Tortoises, but were unsuccessful.

Beagle diary

April 25th 1832

Whilst landing, the boat was swamped and a heavy sea knocked me head over heels and filled the boats. I never shall forget my agony seeing all my useful books, papers, instruments, microscopes etc, gun, rifle, all floating in the salt water; everything is a little injured but not much. I must harden myself to such calamities.

Letter to Caroline Darwin, Botofogo Bay, 25 April 1832

I am afraid you will groan or rather the floor of the lecture room will when the casks arrive. Without you I should be utterly undone. The small cask contains fish: will you open it to see how the spirit has stood the evaporation of the Tropics.

Letter to John Stevens Henslow,
Monte Video,
24th November 1832

Cartoons by Sally Artz

Preservation of Species

One of Darwin’s greatest challenges during the five years of the voyage was to find ways to send back his specimens to England for later study in good condition, and to overcome the ravages of the tropical heat and humidity that could inflict so much damage on fragile and perishable objects.

He sent them back on a variety of passing ships. Henslow had agreed to receive his packages of specimens and store them in Cambridge until his return. Letters to Henslow reveal Darwin’s anxiety about the condition and quality of his specimens.

I have sent to you by the Duke of York Packet …..to Falmouth.— two large casks, containing fossil bones.—a small cask with fish, & a box containing skins, spirit bottle &c & pill-boxes with beetles. Would you be kind enough to open these latter, as they are apt to become mouldy. I am always anxious to hear in what state my things come & any criticisms about quantity or kind of specimens.
Letter to Henslow, Buenos Aires 1832

The long delays in receiving post were frustrating for Darwin who had to wait several months before he received any reply. This reply arrived from Henslow several months later:

Articles in the cask of spirits are spoiled owing to the spirit having escaped through the bung-hole. I have popped the various animals that were in the Keg into fresh spirits in jars & placed them in my cellar— The more delicate things as insects, skins &c. I keep at my own house, with the precaution of putting camphor into the boxes.
Letter to Henslow, 31 August 1833

While some did not survive the long sea journey, the poor condition of others caused problems for Jenyns when studying them a few years later:

One of the Siluridae – very bad and thrown away.
Jenyns Fish in Spirits of Wine

The Loss of Colour

During the nineteenth century biological specimens were preserved in alcohol or, as it was popularly called, ‘spirits of wine’. Darwin sent most of the fish specimens back in wooden casks filled with this preservative. However, it was flammable and caused specimens to shrink, as well as bleaching the colour; hence the importance of the colour notes that Darwin made on board ship at the moment of collection. In his descriptions Jenyns is forced to make a distinction between the colour ‘seen in recent state’ (Darwin’s original observations) and the colour ‘in spirits’ as noted later by Jenyns.

A later development was the use of formalin (a mixture of formaldehyde and water) as a preservative, but it is now known that this damages DNA.

Serranus aspersus – The Dusky grouper

Dark greenish, black above, beneath lighter; sides marked with light emerald green: tips of the anal, caudal, and hinder part of the dorsal, saffron yellow; tips of the pectorals orpiment orange.
Notes made by Darwin on board the Beagle

These colours have been much altered by the action of the spirit. The general ground is now dusky lead, mottled and sprinkled on the sides with dirty white. There is an appearance of four oblong black spots on the upper part of the back beneath the base of the dorsal, not noticed by Mr. Darwin. The tips of the fins have entirely lost their bright colours.
Notes by Jenyns for The Zoology of the Beagle

Dried Skins

Darwin also prepared dried skins on board ship. Taxidermy was an important method of preservation when lack of suitable tight containers made it difficult to keep specimens in liquids. He had learned the skill while enrolled as a medical student in Edinburgh from John Edmonstone, a freed slave who had been taught taxidermy by the naturalist-traveller Charles Waterton. Edmonstone fascinated Darwin with his stories of tropical rain forests in South America and his life as a slave. Darwin’s hatred of slavery caused a disagreement with Captain Fitzroy while on the Beagle.

Above, a dried specimen of Serranus albo-maculatus, The Whitespotted sandbass, collected by Darwin, with an original label (centre) in Jenyns’s handwriting.

Jenyns’s Fishy Problem

On his return to England Darwin found that considerable interest in the voyage had been aroused, chiefly through Henslow’s good efforts in making his observations known in intellectual circles. He was urged to publish descriptions of the specimens he had collected. Lacking the detailed knowledge himself, he began to plan a publication consisting of separate parts, each written by a leading specialist in their field, published as The Zoology of the Beagle. The naturalists he invited were George Waterhouse (Mammals), Richard Owen (Fossil Mammals), John Gould (Birds), Thomas Bell (Reptiles) and Jenyns (Fish). All the parts were edited and included notes by Darwin himself. The project was funded by the British Government.

Six months after his arrival home, Darwin was writing to Jenyns explaining: It would be more satisfactory to myself to see the gleanings of my hands, after having passed through the brains of other naturalists collected together in one work… I myself should have little to do with it; excepting in some orders adding habits and ranges etc and geographical sketches…. I should much like to know what you think about it, and whether you would object to supply the descriptions of the fish to such a work.
Darwin to Jenyns, 10 April 1837

Jenyns was just completing his Manual of British Vertebrates (1836) and felt some reluctance to take on this onerous job: …Darwin urgently pressed me to undertake the Description of his Fishes, which he said he could get no one else to do. Regard for my old friend and the interest I took in all the valuable results of his celebrated voyage, induced me to comply. But the work cost me a deal of labour, and many books had to be consulted on the subject.
Jenyns ‘Chapters in My Life’ 1887

Darwin’s plan was for the work was to appear in four parts published over a number of months with the main new species illustrated by engravings.

Books to Consult

Jenyns made use of books from the Cambridge University Library, especially the last word on the ichthyology at the time, Histoire des Poissons by the French naturalists Georges Cuvier and Achille Valenciennes, published in a weighty 22 volumes and covering 4055 species of fish, a feat of early taxonomy that has been compared in complexity to the mapping of the human genome.

The work cost me a deal of labour…

Jenyns did not consider himself an expert in the study of fish, especially 132 exotic specimens, and wrestled with the dilemma of whether he was suitably qualified to do the work. As the task stretched out over the next four years, he struggled to complete it. Darwin’s good nature and diplomatic skills were frequently employed in keeping him enthused.

Henslow tells me he hears a groan occasionally escape from you when you mention my fishes:

I ought to feel very thoroughly ashamed at this, but I am so very glad that you have undertaken to do what you can, that I am hardly able to pity even your groans.
Darwin to Jenyns, 3 December 1837

He was not even above the occasional jibe aimed at other naturalists:

I would sooner all the fish had rotted, than Mr Gray* described them and with his exception, if you had not taken pity on them they most surely would have remained for many a long year unlooked at and unnamed.
Darwin to Jenyns, 3 December 1837

(*John Edward Gray, the Assistant Keeper of the British Museum, a notorious procrastinator)

Henslow tells me he hears a groan occasionally escape from you when you mention my fishes: I ought to feel very thoroughly ashamed at this, but I am so very glad that you have undertaken to do what you can, that I am hardly able to pity even your groans.
Darwin to Jenyns, 3 December 1837

Pictures on Stone

From the start Darwin intended to have his Zoology of the Beagle illustrated with a selection of significant specimens. Neither Darwin nor Jenyns considered they had any aptitude for drawing: My own utter inability to draw was a far greater disadvantage to me as a Naturalist, than not being a shot. It is noteworthy that Darwin, in his autobiography, laments the same deficiency in himself, saying how much the possession of this art would have assisted him in his Natural History investigations.
Jenyns Chapters in My Life 1887

A search for a suitable artist engraver followed and Darwin settled on Benjamin Waterhouse Hawkins, who had some previous experience illustrating fish. Darwin was concerned about the cost of illustrations. He wrote to Jenyns: Now do you think it very desirable that all these should be engraved? I find the money has gone rather quicker than I anticipated. I must therefore be a little stingy…
Darwin to Jenyns, 14 October 1839

Hawkins was to draw the fish as lithographs on stone, as Darwin described to Jenyns: Mr Hawkins first draws a careful outline, which the Describer inspects and approves, and then he puts this on stone and fills up details from the fish itself…
Darwin to Jenyns, 14 October 1839

There were practical issues too: Will you also tell me to how great a degree you would like the artist to come and lodge at Cambridge?
Darwin to Jenyns, 14 October 1839

Darwin, anxious to keep the project moving, then piles up the pressure on Jenyns: This leads to the important question, how many fish have you in hand, which you could give him at once to work on?…you will see that it would hardly be worth to send him to Cambridge to work with his stones without he could do a good batch there.
Darwin to Jenyns, 14 October 1839

There were inherent drawbacks to lithographic illustration:
You are probably aware that it is one great evil in lithographic engraving, that it is difficult to make many alterations after the drawing is once printed off, in proof…if you come up in the beginning of December you might see the drawings on the stone itself before being printed off… .
Darwin to Jenyns, 17 October 1839

Darwin was juggling his budget and makes constant reference to the fact; the earlier numbers of Zoology of the Beagle had sold for between 8 and 10 shillings, but he felt he had allocated too much of his printing budget to these and was then forced to economise on subsequent volumes, despite the illustrations  being uncoloured.

Benjamin Waterhouse Hawkins

Hawkins’s beautiful and accurate lithographs of the fish in Zoology of the Beagle were informed by his knowledge of comparative anatomy, on which he published several books. Around this time he was producing a wealth of drawings, paintings and lithographs for influential men of science and he became one of England’s most popular illustrators of natural history, part of a movement that was bringing science to the notice of a growing audience in Victorian Britain.

His most lasting influence resides in the commission for a series of ‘antediluvian monsters’ to illustrate Britain’s geological and palaeontological history, which can still be seen at Crystal Palace in London. Later he was asked to produce similar models for Central Park in New York, but the project was unsuccessful and it is said the uncompleted models are buried somewhere in the park.

t took me a long while to complete…

Fish out of water

The physical unpleasantness of inspecting months-old fish that had been caught in tropical climates and packed into wooden barrels to travel halfway round the world must have been seriously trying to a man like Jenyns who was never in robust health.

…you perceive a fishy smell about my book, my silence and I daresay the very name of me. Moreover this fishy smell, a far as I remember of it in Henslow’s Museum was not very savoury, so that I fear the very idea of me must disturb your nostrils….. Could you let me have the fish by the end of November?
Darwin to Jenyns, 15 July 1839

Darwin outlined his ideas as to how the descriptions should be arranged:

..I should think it very desirable that the rudest outline were given of the chief localities from which fish to be described were collected.. – that colours when given were compared with Pat. Syme’s nomenclature book in hand…in what condition of preservation they are in – But you are best judge how far all this is desirable – and perhaps you may have something to say yourself.
Darwin to Jenyns, 17 October 1839

From the correspondence, we can tell that Jenyns had some reservations about the project.

What you say about regretting there was not an earlier selection of the object for figuring applies too truly and with more force to all the other parts of the work. Most people, and I among the rest, learn only by experience and in this case I am never likely to profit by it.
Darwin to Jenyns, 27 October 1839

But the discovery of new species was exhilarating and made the work worthwhile—recalling the thrill of the chase the two men shared in their youth when hunting rare beetles:

I am astonished and glad to hear how many new things you seem to have found – four new genera is something.
Darwin to Jenyns, 26 October 1839

In all Jenyns believed he had identified seventy-five new species, more than half the number collected by Darwin, and seven new genera.

Left: Modern day dissection of a piranha at the Natural History Museum

Publication

The country at first acted like magic on me, but the charm has latterly lost some of its virtue. I am however, a good deal stronger than when in London but I do not feel that I shall have any mental energy for a long time and the Doctors tell me it will be some years before my constitution will recover itself. You and I can tell people in health, they have little idea what an unspeakable advantage they possess over us poor wretches… . I certainly hope your health may improve as the summer passes and follow my and Bell’s example and take your Fish Part easy.
Darwin to Jenyns 24 June 1841

The first part of Volume IV of Zoology of the Beagle—Fish, appeared in January 1840 and the next three over a period of 27 months.

I think the number looks uncommonly well. Several people have approved of it much …. It is good work and will stand its ground, which I wish I could say for my confounded pretty birds.
Darwin to Jenyns, 27 February 1840

Darwin was struggling with the publication of the Birds part of the Zoology and was plagued by ill health in these months, and Richard Owen had been unable to complete the last number of the Fossil Mammal section. Darwin was anxious to convince Jenyns that the four years he had spent on the work had not been wasted:

I most sincerely hope your own satisfaction in producing good stirling work in Natural History will somewhat repay you for your trouble.
Darwin to Jenyns, 5 April 1840

You must feel lightened of no inconsiderable load, having finished the Fish – I was looking at the last number yesterday – what a mass of matter there is in it! – The conviction I feel that your Part is real good work, I assure you, is a very great satisfaction to me.
Darwin to Jenyns 9 May 1842

I rated the book as one of my two most important works, along with my Manual of British Vertebrate Animals.
Jenyns, Chapters in My Life 1887

Lifelong Friends

Beyond the publication of his work on the Beagle fishes, Jenyns continued his friendship and correspondence with Darwin.

Darwin drew upon Jenyns’s broad knowledge of natural history and frequently enquired about his observations on a particular topic, often relating to variations within and between species. Jenyns was even one of the recipients of a questionnaire, Questions About the Breeding of Animals , that Darwin issued in 1839. However, Jenyns was not an expert in selective breeding and it is not clear whether he replied.

Jenyns was one of the very few naturalists that Darwin trusted with the generalities of his evolutionary theories from quite early on in their conception. In a letter to Jenyns in 1844 he wrote:

The general conclusion, at which I have slowly been driven from a direct opposite conviction, is that species are mutable and that allied species are co-descendants of common stock … I shall not publish on this subject for several years.
Darwin to Jenyns, 12 October 1844

In his next letter to Jenyns, he defended this statement and hinted at the mechanism of natural selection:

A long searching amongst agricultural and horticultural books and people makes me believe (I well know how absurdly presumptuous this must appear) that I see the way in which new varieties become exquisitely adapted to the external conditions of life, and to other surrounding beings. – I am a bold man to lay myself open to being thought such a fool, and a most deliberate one.
Darwin to Jenyns, 25 November 1844

Darwin did not publish ‘On the Origin of Species by Means of Natural Selection’ for another fifteen years but when he did (24 November 1859), he was quick to seek Jenyns’s opinion:

My dear Jenyns
I must thank you for your very kind note forwarded to me from Down. I have been much out of health this summer & have been hydropathising here, for last six weeks with very little good as yet.— I shall stay here for another fortnight at least.
Please remember that my Book is only an abstract & very much condensed & to be at all intelligible must be carefully read. I shall be very grateful for any criticisms. But I know perfectly well that you will not at all agree with the lengths which I go. It took long years to convert me. I may of course be egregiously wrong; but I cannot persuade myself that a theory which explains (as I think it certainly does) several large classes of facts, can be wholly wrong; notwithstanding the several difficulties which have to be surmounted somehow, & which stagger me even to this day.
I wish that my health had allowed me to publish in extenso; if I ever get strong enough I will do so, as the greater part is written out, & of which M.S. the present volume is an abstract.—
I fear this note will be almost illegible; but I am poorly & can hardly sit up.

Jenyns was equally quick to read it and respond, supporting some aspects of the theory while challenging others, as can be seen from the transcribed letters reproduced below:

My dear Darwin
I have read your interesting book with all carefulness as you enjoined,—have gleaned a great deal from it, & consider it one of the most valuable contributions to Nat. Hist Literature of the present day. Perhaps you may like to know what I think of your particular theory, tho` you will doubtless have many opinions offered far more deserving to be weighed than mine.
As you are aware, I am no stickler for the multitude of so-called species created by so many naturalists of late years, & I always thought the time was not distant—when, after the brainsplitting process had been carried to it’s utmost length—some at least could see the necessity of retracing their steps, & again uniting a large number of the forms they had so carefully separated. But I frankly confess I did not look for any such large assemblages of species to be brought together in this way, as the descendants from one & the same stock, similar to what you have attempted in your volume. By this you will see that I embrace yr theory in part, but hardly to the full extent to which you carry it. Still I allow you have made out a very strong case, and I will not pretend to say what future researches in the same direction may not ultimately establish.
I can quite fall in with the view that those fossil animals which so closely resemble their living representatives at the present day, are in fact the progenitors of these last;—such indeed has been my opinion for many years, tho’ a contrary one, I know had been adopted by many of our first Geologists & Naturalists. I can also well believe that whole families have had a common parentage at some remote period of the past,—& that the same may have been the case, reasoning analogically (tho’ this is not always safe in Nat. Hist. speculations),—with groups of even higher denomination. But I cannot think that all the difficulties which stand in
the way of so extensive a generalization have been entirely got over—
One great difficulty to my mind in the way of your theory is the fact of the existence of Man. I was beginning to think you had entirely passed over this question, till almost in the last page I find you saying that `light will be thrown on the origin of man & his history’. By
this I suppose is meant that he is to be considered a modified & no doubt greatly improved orang! I doubt if this will find acceptance with the generality of readers— I am not one of those in the habit of mixing up questions of science & scripture, but I can hardly see what sense or meaning is to be attached to Gen: 2.7. & yet more to vv. 21. 22, of the same chapter, giving an account of the creation of woman,—if the human species at least has not been created independently of other animals, but merely come into the world by ordinary descent from previously existing races—whatever those races may be supposed to have been. Neither can I easily bring myself to the idea that man’s reasoning faculties & above all his moral sense, cd. ever have been obtained from irrational progenitors, by mere natural selection—acting however gradually & for whatever length of time that may be required. This seems to be doing away altogether with the Divine Image which forms the insurmountable distinction between man & brutes.
Jenyns to Darwin, 4 January 1860

My dear Jenyns
I am very much obliged for your letter. It is of great use & interest to me to know what impression my Book produces on philosophical & instructed minds. I thank you for the kind things which you say; & you go with me much further than I expected.— You will think it presumptuous, but I am convinced, if circumstances lead you to keep the subject in mind, that you will go further. No one has yet cast doubt on my explanation of the subordination of group to group, on homologies, Embryology & Rudimentary organs; & if my explanation of these classes of facts be at all right, whole classes of organic beings must be included in one line of descent.— The imperfection of the geological Record is one of greatest difficulties (by the way, Lyell, who is convert, does not think that I have exaggerated imperfection). During earliest period the record would be most imperfect, & this seems to me sufficiently to account for our not finding intermediate forms between the classes in the same great Kingdoms.—
It was certainly rash in me putting in my belief of probability of all beings having descended from one primordial form; but as this seems yet to me probable, I am not willing to strike it out.— Huxley alone supports me in this, & something could be said in its favour.—
With respect to man, I am very far from wishing to obtrude my belief; but I thought it dishonest to quite conceal my opinion.— Of course it is open to everyone to believe that man appeared by separate miracle, though I do not myself see the necessity or probability.—
Pray accept my sincere thanks for your kind note. Your going some way with me gives me great confidence that I am not very wrong. For a very long time I halted half-way; but I do not believe that any enquiring mind will rest half-way. People will have to reject all or admit all,—by all I mean only the members of each great Kingdom.—
My dear Jenyns
Yours most sincerely
C. Darwin
Darwin to Jenyns, 7 January 1860

Despite not meeting in their later years, the warmth of feeling the two friends maintained can be seen in these extracts from the last letters they exchanged:

It must be a great satisfaction to you in the evening of life to think that your researches, so multifarious and at the cost of so much health and trouble have come at length to be duly appreciated; and that both you and your theories have outlived the fierce opposition that was made to them when you first set them before the scientific world. You, it appears, have just entered your 70th year. I, in a very little more than two months shall be entering my 78th … How few naturalists of the present day there must be who have known you longer than myself – or so long.
Jenyns to Darwin, 12 March 1877

Your extremely kind letter has given me warm pleasure. As one grows old one’s thoughts turn to the past rather than to the future, and I often think of the pleasant and to me valuable hours which I spent with you on the borders of the fens…
I suppose that I shall go on as long as I can without obviously making a fool of myself. I have a great mass of matter with respect to variation under nature, but so much has been published since the appearance of the Origin of Species, that I very much doubt whether I retain power of mind and thought to reduce the mass into a digested whole. I have sometimes thought that I would try, but dread the attempt.
Darwin to Jenyns, 13 March 1877