April 6, 1874. 



W. T. Harris, President, in the chair. 



Fourteen members present. 



Publications received, laid upon the table. 



A paper "On the Climatic Changes of Illinois and their Caus- 

 es," by Mr. Amos Sawyer, was read and referred to the Publica- 

 tion Committee after having elicited some discussion. 



Judge Holmes called attention to an article in the "American 

 Journal of Science and Arts," by Prof. O. H. Marsh, which very 

 strongly supported the hypothesis of evolution by decrease of toes 

 in the fossil Uitgulata. 



Prof. Marsh, in discussing the genesis of the Horse, suggested that the 

 line of descent was through Oro/iippus, of the Eocene ; Mio/iippas, and 

 Anchitherium, of the Miocene; Anckippus, Hipparion, Prolo/iippus, and 

 Pliohippus, of the Pliocene; and Equus, of the Quaternary and recent. 

 Oro/iippus has all four digits on the fore-foot; in Miohippus the fourth 

 has disappeared; in Hippario?i there are three, but the outer ones are too 

 short to be of any use; while in Equus they are represented only by rudi- 

 mentary splint bones. He thought that while it is plain that the change 

 from the cretaceous 5-toed vertebrates involved some kind of continuation, 

 the problem was to get at a conception of the mode and manner of that 

 continuation. Continuous descent as from father to son — from individual 

 to individual — was an erroneous conception. Descent is only from the 

 pair, and there is an interweaving of pairs until all are related. The indi- 

 vidual perishes, and nothing continues to live or to change but the type, or 

 the ideal species. This view presents us with the true conception of the 

 doctrine of evolution ; and so conceived that doctrine would cease to be 

 so objectionable. Such a conception is in harmony with the idea of new 

 creation and also of evolution. 



Mr. Riley thought the process of evolution was not a matter of 

 conception but of fact ; that modification through climatic changes, 

 natural selection, and the other natural influences now recognized 

 by evolutionists, were suffic ent to account for the origin of spe- 

 cies ; and that to conceive of the modification through any other 

 means than descent was begging the question, and only another 

 way of expressing the old idea of special creation. 



Mr. Todd presented two newspaper accounts of the late terrific 

 storm at Alton, Ills., for preservation in the records. 



Mr. E. Harvey was elected an Associate Member. 



