SKETCH OF PROFESSOR HUXLEY. 741 



among his countrymen. When we say the first zoologist, we give the 

 widest and fullest signification to the word " zoology " which the latest 

 developments of this science demand. Zoology is, in this sense, the 

 entire biology of animals ; and we accordingly consider as essential 

 parts of it the whole field of Animal Morphology and Physiology, in- 

 cluding not only Comparative Anatomy and Embryology, but also 

 Systematic Zoology, Paleontology, and Zoological Philosophy. We 

 look upcn it as a special merit in Prof. Huxley that he has a thor- 

 oughly broad conception of the science in which he labors, and that, 

 with a most careful empirical acquaintance with individual phenom- 

 ena, he combines a clear philosophical appreciation of general rela- 

 tions. 



When we consider the long series of distinguished memoirs with 

 which, during the last quarter of a century, Prof. Huxley has enriched 

 zoological literature, we find that in each of the larger divisions of the 

 animal kingdom we are indebted to him for important discoveries. 



From the lowest animals, he has gradually extended his investiga- 

 tions up to the highest, and even to man. His earlier labors were, for 

 the most part, occupied with the lower marine animals, especially with 

 the pelagic organisms swimming at the surface of the open sea. He 

 availed himself of an excellent opportunity for the study of these, 

 when on board H. M. S. Rattlesnake on a voyage of circumnavigation, 

 which took him to many most interesting parts of tropical oceans lit- 

 tle investigated, previously, by the zoologist ; especially the coasts of 

 Australia. Here he was able to observe, in their living state, a host 

 of lower pelagic animals, some of which had not at all been studied, 

 others but imperfectly. In the Protozoa, he was the first to lead us 

 to satisfactory conclusions concerning the nature of the puzzling Tha- 

 lassicollidse and Sphaerozoida. Our knowledge of Zoophytes has been 

 greatly extended by his splendid work on " Oceanic Hydrozoa," in 

 which, chiefly, the remarkable Siphonophora, with their largely-de- 

 veloped polymorphism and the instructive division of labor in their 

 individual organs, are described with very great accuracy. 



Already in his first work u On the Anatomy and Affinities of the 

 Medusae," 1849, he directed attention to the very important point, 

 that the body of these animals is constructed of two cell-layers — of 

 the Ectoderm and the Endoderm — and that these, physiologically and 

 morphologically, may be compared to the two germinal layers of the 

 higher animals. He has made us better acquainted with several in- 

 teresting members of the class Vermes, Sagitta, Lacinularia, some 

 lower Annulosa, etc. He was the first to point out the? affinities of 

 Echinodermata with Vermes. In opposition to the old view, that the 

 Echinodermata belong to the Radiata, and, on account of their radial 

 type, are to be classed with corals, medusae, etc., Huxley showed that 

 the whole organization of the former is essentially different from that of 

 the latter, and th^t the Echinoderms are more nearly related, morpho- 



