[A few days later he writes to his son:—]
The Liberals are making fools of themselves, and "the family" declare I am becoming a Jingo! another speech from Gladstone is expected to complete my conversion.
[Among other occupations he still had to attend the Scottish Universities Commission, for which he wrote the paragraph on examinations in its report; he lectured on the Hand at the Working Men's College; prepared new editions of the "Physiography," "Elementary Physiology," and "Vertebrate Anatomy," and at length brought out the "Introductory Primer" in the Science Primer Series, in quite a different form from what he had originally sketched out. But his chief interest lay in the Invertebrata. From April 29 to June 3 he lectured to working men at Jermyn Street upon the Crayfish; read a paper on the Classification and Distribution of Crayfishes at the Zoological Society on June 4, and lectured at the Zoological Gardens weekly from May 17 to June 21 on Crustaceous Animals. In all this work lay the foundations of his subsequent book on the Crayfish, which I find jotted down in the notes of this year to be written as an introduction to "Zoology," together with the "Dog" as an introduction to the "Mammalia", and "Man"—already dealt with in "Man's Place in Nature"—as an introduction to "Anthropology." This projected series is completed with a half-erased note of an introduction to "Psychology," which perhaps found some expression in parts of the "Hume," also written this year.
He notes down also, work on the Ascidians, and on the morphology of the Mollusca and Cephalopods brought back by the "Challenger," in connection with which he now began the monograph on the rare creature Spirula, a remarkable piece of work, being based upon the dissections of a single specimen, but destined never to be completed by his hand, though his drawings were actually engraved, and nothing remained but to put a few finishing touches and to write detailed descriptions of the plates.
Letters to W.K. Parker and Professor Haeckel touch on this part of his work; the former, indeed, offering a close parallel to a story, obviously of the same period, which the younger Parker tells in his reminiscences, to illustrate the way in which he would be utterly engrossed in a subject for the time being. Jeffery Parker, while demonstrator of biology, came to him with a question about the brain of the codfish at a time when he was deep in the investigation of some invertebrate group.] "Codfish?" [he replied,] "that's a vertebrate, isn't it? Ask me a fortnight hence, and I'll consider it."
4 Marlborough Place, September 25, 1878.
My dear Parker,
As far as I recollect Ammocoetes is a vertebrated animal—and I ignore it.
The paper you refer to was written by my best friend—a carefulish kind of man—and I am as sure that he saw what he says he saw, as if I had seen it myself.
But what the fact may mean and whether it is temporary or permanent—is thy servant a dog that he should worry himself about other things with backbones? Not if I know it.