The most important of the unfinished work consists of the long-delayed “Oceanic Hydrozoa,” the “Manual of Comparative Anatomy,” and a report on Fisheries. The rest of the unfinished programme shows the usual commixture of technical studies in anatomy and paleontology, with essays on the philosophical and educational bearings of his work. On the one hand are memoirs of Daphnia, Nautilus, and the Herring, the affinities of the Paleozoic Crustacea, the Ascidian Catalogue and Positive Histology; on the other, the Literature of the Drift, a review of the present state of philosophical anatomy, and a scheme for arranging the Explanatory Catalogue to serve as an introductory textbook to the Jermyn Street lectures and the paleontological demonstrations. Here, too, would fall a proposed “Letter on the Study of Comparative Anatomy,” to do for those subjects what Henslow had done in his “Letter” for Botany.
In addition to the fact of his being forced to take up Paleontology, it was perhaps the philosophic breadth of view with which he regarded his subject at any time, and the desire of getting to the bottom of each subsidiary problem arising from it, that made him for many years seem constantly to spring aside from his own subject, to fly off at a tangent from the line in which he was assured of unrivalled success did he but devote to it his undivided powers. But he was prepared to endure the charge of desultoriness with equanimity. In part, he was still studying the whole field of biological science before he would claim to be a master in one department; in part, he could not yet tell to what post he might succeed when he left—as he fully expected to leave—the Professorship at Jermyn Street.
One characteristic of his early papers should not pass unnoticed. This was his familiarity with the best that had been written on his subjects abroad as well as in England. Thoroughness in this respect was rendered easier by the fact that he read French and German with almost as much facility as his mother tongue. “It is true, of course, that scientific men read French and German before the time of Huxley; but the deliberate consultation of all the authorities available has been maintained in historical succession since Huxley’s earliest papers, and was absent in the papers of his early contemporaries.” (P. Chalmers Mitchell in “Natural Science” August 1895.)
About this time his activity in several branches of science began to find recognition from scientific societies at home and abroad. In 1857 he was elected honorary member of the Microscopical Society of Giessen; and in the same year, of a more important body, the Academy of Breslau (Imperialis Academia Caesariana Naturae Curiosum). He writes to Hooker:—]