ib94. OBITUARY. 153 



considerably more than a hundred new ones, drawn , by the author 

 himself direct from nature. 



Like other books which Marshall published either alone or con- 

 jointly, this was intended as a laboratory manual, and hence the 

 "type system" had to be adopted; but it was really adopted for 

 another reason. He was keenly alive to a source of error which is 

 too commonly ignored — the assumption that what is true of one 

 animal is true also of its allies, or nearly so. It is this assumption 

 which seems to be taken implicitly as a justification for the description 

 of changes in the course of development of man, which, whether they 

 occur or not, have not been seen by those who have described them, 

 or by those who have been quoted. It is this, also, that leads to the 

 wholesale^illustration of books on human anatomy by figures intended 

 to illustrate the structure of man, though they have been drawn from 

 animals sometimes as unlike man as dogfishes and birds. " Com- 

 parative Embryology " is one thing : the indiscriminate confusion of 

 the embryonic development of one animal with that of another is 

 another thing altogether. Marshall has produced the first book on 

 the development of man and other vertebrates which is free from this 

 confusion. He felt strongly the necessity for having a straightforward 

 description of the development from beginning to end of a few typical 

 vertebrates before attacking anew the larger problems of comparative 

 embryology. That he did not live to attack anew those larger 

 problems is a pity too sad for expression in words. 



Besides this great embryological work, he published, alone and 

 conjointly with others, several papers on vertebrate morphology, and 

 especially on the morphology of the head. Other papers dealt with 

 the development of the kidneys and fat-bodies, the abnormal condi- 

 tions of the reproductive organs, and the development of the blood- 

 vessels of the frog. 



His chief invertebrate work was upon the Pennatulida, and one 

 of the papers on this subject was written in collaboration with his 

 father. He worked also upon the structure and physiology of 

 Antedon {Comatnla), and published a paper on its nervous system. 



His published lectures and addresses are numerous, the 

 presidential address to the Biological Section of the British Associa- 

 tion (Leeds, 1890) and a paper on the morphology of the sexual 

 organs of Hydra being, perhaps, the most important of them. 



This may seem a small amount of scientific work for a man of 

 his age, but those who knew Marshall best, know best how small a 

 fraction it is of the work he did for the advancement of learning. 

 They who would judge him by his published work would do him a 

 gross injustice. 



There is no great scarcity of zoologists who might efficiently 

 perform the strictly zoological work of the professorship, but it is not 

 probable that a successor will be found who is willing to devote so 

 much time and energy to other business of the College and University 



