194 LEADING AMERICAN MEN OF SCIENCE 



"At present I am giving a few lectures on Embryology and its 

 bearing on Evolution in general. It is a curious fact that the op- 

 ponents of evolution have as yet started no theory except the pre- 

 posterous one of immediate creation of each species. They simply 

 deny. After many trials I have never been able to get Agassiz to 

 commit himself to even the most general statement of a concep- 

 tion. He was just the man who ought to have taken up the evo- 

 lution theory and worked it into a good shape, which his knowl- 

 edge of embryology and palaeontology would have enabled him 

 to do. He has lost a golden opportunity, but there is no use in 

 talking of that." l 



That this divergence upon a vital question did not estrange them 

 personally is greatly to the credit of both these great men. 



In the posthumous paper on the shell-heaps of Florida, 2 which 

 Packard believes to have been written in 1873 or early in 1874, 

 he reiterates his general view and in a way applies it to the early 

 stages of the human species: 



"The steady progress of discovery justifies the inference that 

 man, in the earliest periods of his existence of which we have 

 knowledge, was at the best a savage, enjoying the advantage of a 

 few rude inventions. According to the theory of evolution, which 

 has the merit of being based upon and not being inconsistent with 

 observed analogies and processes of nature, he must have gone 

 through a period when he was passing out of the animal into the 

 human state, when he was not yet provided with tools of any 

 sort, and when he lived simply the life of a brute." 



The question of Abiogenesis ("spontaneous generation") was 

 considered by Wyman with his habitual caution. He performed 

 two extensive series of experiments with flasks 3 containing boiled 

 solutions of organic matter. The earlier (1862) seemed to indi- 



1 In his memoir (referred to on p. 172, note) Asa Gray relates a conversa- 

 tion in which Wyman expressed the same regret and recalled a conversation 

 of his own with Agassiz, when the latter said that Humboldt had told him 

 that Cuvier missed a great opportunity in taking sides against St. Hilaire. 



2 Fresh-water Shell-mounds of the St. Johns River, Florida. Fourth 

 memoir. Peabody Academy of Science, Salem, Mass., 1875. 



3 One of these historic flasks has been appropriately placed in the charge 

 of Theobald Smith, M. D., Professor of Comparative Pathology in Harvard 

 University. 



