APPENDIX 1.
As for this unfinished work, suggestive outlines left for others to fill in, Professor Howes writes to me in October 1899:—
Concerning the papers at South Kensington, which, as part of the contents of your father's book-shelves, were given by him to the College, and now are arranged, numbered, and registered in order for use, there is evidence that in 1858 he, with his needles and eyeglass, had dissected and carefully figured the so-called pronephros of the Frog's tadpole, in a manner which as to accuracy of detail anticipated later discovery. Again, in the early '80's, he had observed and recorded in a drawing the prae-pulmonary aortic arch of the Amphibian, at a period antedating the researches of Boas, which in connection with its discovery placed the whole subject of the morphology of the pulmonary artery of the vertebrata on its final basis, and brought harmony into our ideas concerning it.
Both these subjects lie at the root of modern advances in vertebrate morphology.
Concerning the skull, he was in the '80's back to it with a will. His line of attack was through the lampreys and hags and the higher cartilaginous fishes, and he was following up a revolutionary conception (already hinted at in his Hunterian Lectures in 1864, and later in a Royal Society paper on Amphioxus in 1875), that the trabeculae cranii, judged by their relationships to the nerves, may represent a pair of prae-oral visceral arches. In his unpublished notes there is evidence that he was bringing to the support of this conclusion the discovery of a supposed 4th branch to the trigeminal nerve—the relationships of this (which he proposed to term the "hyporhinal" or palato-nasal division) and the ophthalmic (to have been termed the "orbitonasal" (A term already applied by him in 1875 to the corresponding nerve in the Batrachia. ("Encyclopaedia Britannica" 9th edition, volume 1 article "Amphibia."))) to the trabecular arch and a supposed prae-mandibular visceral cleft, being regarded as repetitional of those of the maxillary and mandibular divisions to the mandibular cleft. So far as I am aware, von Kupffer is the only observer who has given this startling conclusion support, in his famous "Studien" (Hf. I. Kopf Acipenser, Munchen, 1893), and from the nature of other recent work on the genesis of parts of the cranium hitherto thought to be wholly trabecular in origin, it might well be further upheld. As for the discovery of the nerve, I have been lately much interested to find that Mr. E. Phelps Allis, junior, an investigator who has done grand work in Cranial Morphology, has recently and independently arrived at a similar result. It was while working in my laboratory in July last that he mentioned the fact to me. Remembering that your father had published the aforementioned hints on the subject, and recalling conversations I had with him, it occurred to me to look into his unpublished manuscripts (then being sorted), if perchance he had gone further. And, behold! there is a lengthy attempt to write the matter up in full, in which, among other things, he was seeking to show that, on this basis, the mode of termination of the notochord in the Craniata, and in the Branchiostomidae (in which the trabecular arch is undifferentiated), is readily explained. Mr. Allis's studies are now progressing, and I have arranged with him that if, in the end, his results come sufficiently close to your father's, he shall give his work due recognition and publicity. (See "The Lateral Sensory Canals, the Eye-Muscles, and the Peripheral Distribution of certain of the Cranial Nerves of Mustelus laevis" by Edward Phelps Allis, junior, reprinted from "Quarterly Journal Micr. S." volume 45 part 2 New Series.)
Among his schemes of the early '80's, there was actually commenced a work on the principles of Mammalian Anatomy and an Elementary Treatise on the Vertebrata. The former exists in the shape of a number of drawings with very brief notes, the latter to a slight extent only in manuscript. In the former, intended for the medical student and as a means of familiarising him with the anatomical "tree" as distinct from its surgical "leaves," your father once again returned to the skull, and he leaves a scheme for a revised terminology of its nerve exits worthy his best and most clear-headed endeavours of the past. (Concerning this he wrote to Professor Howes in 1890 when giving him permission to denote two papers which he was about to present to the Zoological Society, as the first which emanated from the Huxley Research Laboratory]:—"Pray do as you think best about the nomenclature. I remember when I began to work at the skull it seemed a hopeless problem, and years elapsed before I got hold of the clue." [And six weeks later, he writes]:—"You are always welcome to turn anything of mine to account, though I vow I do not just now recollect anything about the terms you mention. If you were to examine me in my own papers, I believe I should be plucked.") [And well do I remember how, in the '80's, both in the class-room and in conversation, he would emphasise the fact that the hypoglossus nerve roots of the mammal arise serially with the ventral roots of the spinal nerves, little thinking that the discovery by Froriep, in 1886, of their dorsal ganglionated counterparts, would establish the actual homology between the two, and by leading to the conclusion that though actual vertebrae do not contribute to the formation of the mammalian skull, its occipital region is of truncal origin, mark the most revolutionary advance in cranial morphology since his own of 1856.
Much of the final zoological work of his life lay with the Bony Fishes, and he leaves unfinished (indeed only just commenced) a memoir embodying a new scheme of classification of these, which shows that he was intending to do for them what he did for Birds in the most active period of his career. It was my good fortune to have helped as a hodman in the study of these creatures, with a view to a Text-book we were to have written conjointly, and as I realise what he was intending to make out of the dry facts, I am filled with grief at the thought of what we must have lost. His classification was based on the labours of years, as testified by a vast accumulation of rough notes and sketches, and as a conspicuous feature of it there stands the embodiment under one head of all those fishes having the swim-bladder in connection with the auditory organ by means of a chain of ossicles—a revolutionary arrangement, which later, in the hands of the late Dr. Sagemahl, and by his introduction of the famous term—"Ostariophyseae," has done more than all else of recent years to clear the Ichthyological air. Your father had anticipated this unpublished, and in a proposal to unite the Herrings and Pikes into a single group, the "Clupesoces," he had further given promise of a new system, based on the study of the structure of the fins, jaws, and reproductive organs of the Bony Fishes, the classifications of which are still largely chaotic, which would have been as revolutionary as it was rational. New terms both in taxonomy and anatomy were contemplated, and in part framed. His published terms "Elasmo-" and "Cysto-arian" are the adjective form of two—far-reaching and significant—which give an idea of what was to have come. Similarly, the spinose fin-rays were to have been termed "acanthonemes," the branching and multiarticulate "arthronemes," and those of the more elementary and "adipose fin" type "protonemes": and had he lived to complete the task, I question whether it would not have excelled his earlier achievements.
The Rabbit was to have been the subject of the first of the aforementioned books, and in the desire to get at the full meaning of problems which arose during its progress, he was led to digress into a general anatomical survey of the Rodentia, and in testimony to this there remain five or six books of rough notes bearing dates 1880 to 1884, and a series of finished pencil-drawings, which, as works of art and accurate delineations of fact, are among the most finished productions of his hand. In the same manner his contemplated work upon the Vertebrata led him during 1879-1880 to renewed investigation of the anatomy of some of the more aberrant orders. Especially as concerning the Marsupialia and Edentata was this the case, and to the end in view he secured living specimens of the Vulpine Phalanger, and purchased of the Zoological Society the Sloths and Ant-eaters which during that period died in their Gardens. These he carefully dissected, and he leaves among his papers a series of incomplete notes (fullest as concerning the Phalanger and Cape Anteater [Orycteropus] ([I was privileged to assist in the dissection of the latter animal, and well do I remember how, when by means of a blow-pipe he had inflated the bladder, intent on determining its limit of distensibility, the organ burst, with unpleasant results, which called forth the remark] "I think we'll leave it at that!")), which were never finished up.
They prove that he intended the production of special monographs on the anatomy of these peculiar mammalian forms, as he did on members of other orders which he had less fully investigated, and on the more important groups of fishes alluded to in the earlier part of my letter; and there seems no doubt, from the collocation of dates and study of the order of the events, that his memorable paper "On the Application of the Laws of Evolution to the arrangement of the Vertebrata, and more particularly of the Mammalia," published in the "Proceedings of the Zoological Society" for 1880,—the most masterly among his scientific theses—was the direct outcome of this intention, the only expression which he gave to the world of the interaction of a series of revolutionary ideas and conceptions (begotten of the labours of his closing years as a working zoologist) which were at the period assuming shape in his mind. They have done more than all else of their period to rationalise the application of our knowledge of the Vertebrata, and have now left their mark for all time on the history of progress, as embodied in our classificatory systems.
He was in 1882 extending his important observations upon the respiratory apparatus from birds to reptiles, with results which show him to have been keenly appreciative of the existence of fundamental points of similarity between the Avian and Chelonian types—a field which has been more recently independently opened up by Milani.
Nor must it be imagined that after the publication of his ideal work on the Crayfishes in 1880, he had forsaken the Invertebrata. On the contrary, during the late '70's, and on till 1882, he accumulated a considerable number of drawings (as usual with brief notes), on the Mollusca. Some are rough, others beautiful in every respect, and among the more conspicuous outcomes of the work are some detailed observations on the nervous system, and an attempt to formulate a new terminology of orientation of the Acephalous Molluscan body. The period embraces that of his research upon the Spirula of the "Challenger" expedition, since published; and incidentally to this he also accumulated a series of valuable drawings, with explanatory notes, of Cephalopod anatomy, which, as accurate records of fact, are unsurpassed.
As you are aware, he was practically the founder of the Anthropological Institute. Here again, in the late '60's and early '70's, he was most clearly contemplating a far-reaching inquiry into the physical anthropology of all races of mankind. There remain in testimony to this some 400 to 500 photographs (which I have had carefully arranged in order and registered), most of them of the nude figure standing erect, with the arm extended against a scale. A desultory correspondence proves that in connection with these he was in treaty with British residents and agents all over the world, with the Admiralty and naval officers, and that all was being done with a fixed idea in view. He was clearly contemplating something exhaustive and definite which he never fulfilled, and the method is now the more interesting from its being essentially the same as that recently and independently adopted by Mortillet.
Beyond this, your father's notes reveal numerous other indications of matters and phases of activity, of great interest in their bearings on the history and progress of contemporary investigation, but these are of a detailed and wholly technical order.