His published ethnological papers (says Sir Michael Foster) are not numerous, nor can they be taken as a measure of his influence on this branch of study.  In many ways he has made himself felt, not the least by the severity with which on the one hand he repressed the pretensions of shallow persons who, taking advantage of the glamour of the Darwinian doctrine, talked nonsense in the name of anthropological science, and on the other hand, exposed those who in the structure of the brain or of other parts, saw an impassable gulf between man and the monkey.  The episode of the “hippocampus” stirred for a while not only science but the general public.  He used his influence, already year by year growing more and more powerful, to keep the study of the natural history of man within its proper lines, and chiefly with this end in view held the Presidential Chair of the Ethnological Society in 1869-70.  It was mainly through his influence that this older Ethnological Society was, a year later, in 1871, amalgamated with a newer rival society, the Anthropological, under the title of “The Anthropological Institute.”

During this time he was constantly occupied with paleontological work, as the following letter to Sir Charles Lyell indicates:—­]

Jermyn Street, November 27, 1865.

My dear Sir Charles,

I returned last night from a hasty journey to Ireland, whither I betook myself on Thursday night, being attracted vulture-wise by the scent of a quantity of carboniferous corpses.  The journey was as well worth the trouble as any I ever undertook, seeing that in a morning’s work I turned out ten genera of vertebrate animals of which five are certainly new; and of these four are Labyrinthodonts, amphibia of new types.  These four are baptised Ophiderpeton, Lepterpeton, Ichthyerpeton, Keraterpeton.  They all have ossified spinal columns and limbs.  The special interest attaching to the two first is that they represent a type of Labyrinthodonts hitherto unknown, and corresponding with Siren and Amphiuma among living Amphibia.  Ophiderpeton, for example, is like an eel, about three feet long with small fore legs and rudimentary hind ones.

In the year of grace 1861, there were three genera of European carboniferous Labyrinthodonts known, Archegosaurus, Scleroceplus, Parabatrachus.

The vertebral column of Archegosaurus was alone known, and it was in a remarkably imperfect state of ossification.  Since that date, by a succession of odd chances, seven new genera have come into my hands, and of these six certainly have well-ossified and developed vertebral columns.

I reckon there are now about thirty genera of Labyrinthodonts known from all parts of the world and all deposits.  Of these eleven have been established by myself in the course of the last half-dozen years, upon remains which have come into my hands by the merest chance.

Five and twenty years ago, all the world but yourself believed that a vertebrate animal of higher organisation than a fish in the carboniferous rocks never existed.  I think the whole story is not a bad comment upon negative evidence.