OF ARTS AND SCIENCES. 411 



Professor Bowen raised similar objections; contending that 

 tliis hypothesis is one of cosmogony rather than of natural 

 history, and makes such huge demands upon time, that the 

 indefinite becomes virtually infinite time, so rendering the 

 theory dependent on metaphysical rather than inductive 

 reasoning ; he denied the validity of all reasoning from the 

 variability of plants to that of animals, or that the two had 

 enough in common to warrant inferences from the one to 

 the other; he also denied the variability of instinct in any 

 animals, or that there was any evidence of the heritability 

 of variations of structure or instinct except in a few sporadic 

 cases, and in these only for two or three generations. He in- 

 sisted that there was no reason why, on the theory, instinct 

 and structure should vary contemporaneously ; and finally he 

 maintained that the theory denied the doctrine of the per- 

 manence of type, as received by all naturalists, was incom- 

 patible with the whole doctrine of final causes, and negatived 

 design or purpose in the animate or organic world. 



Four hnudred and eiglitietlx meeting. 



April 10, 1860. — Monthly Meeting. 



The President in the chair. 



Professor Horsford introduced Mr. Du Chaillu, who, invited 

 by the Academy, gave some account of his travels in Western 

 Africa, and of his observations of the habits of the Gorilla. 



Professor Gray criticised in detail several of the positions 

 taken at the preceding meeting by Mr. Lowell, Professor 

 Bowen, and Professor Agassiz respectively ; — premising that 

 he had no doubt that variation and natural selection would 

 have to be admitted as operative in nature, but were prob- 

 ably inadequate to the work which they had been put to. 

 He maintained : — 



1. That varieties abundantly occur in nature, at least among plants ; 

 and that very fcAv of them can be of hybrid origin ; that hybridation 



