BUFFALO SOCIETY OF NATURAL SCIENCES 1 79 



of fish obtained from the head waters of the four rivers, five were 

 found by Mr. Cope on both sides of the water-shed. There is like- 

 wise considerable disparity in the genera represented in the different 

 rivers. The still more important barrier of the Rocky Mountains 

 separates ichthyological areas yet more sharply marked off from each 

 other. Such isolated basins as Lake Baikal, Lake Titicaca, and the 

 Caspian Sea show by their peculiar assemblages of fishes how much 

 ichthyic types may be modified by prolonged isolation. The differ- 

 ences, therefore, between the fauna of Lake Orcadie and Lake Cale- 

 donia during the Old Red Sandstone, as I venture to hold, are not 

 incompatible with the idea that the two lakes were in a general and 

 geological sense contemporaneous, though separated from each other 

 by the barrier of the Grampian Mountains, which formed an effectual 

 boundary between two ichthyic faunas" (71, 364, 365). 



Deposition in the Sea. To certain geologists it will appear that 

 I am wasting paper in setting forth a theory which has as its thesis 

 the deposition of the Old Red sandstone in the sea, and that it is a 

 further useless expenditure of ink and of the reader's time for me to 

 voice the objections to such a theory. Indeed, I would agree with 

 anyone who raised such a protest were it not for the deplorable fact 

 that there are still not a few geologists who claim that this much- 

 talked-of red sandstone was deposited in the sea, and further that 

 other sandstones with similar striking lithological and faunal charac- 

 teristics could have been formed nowhere else but in that region where 

 all sediments have been deposited since the world began, namely, in 

 the littoral zone of the sea. 



The chief advocates for the theory of marine deposition are Mac- 

 nair and Reid who brought out two papers in the Geological Magazine 

 for 1896, one entitled "On the Physical Conditions under which the 

 Old Red Sandstone of Scotland Was Deposited" (159), and the other 

 "Palaeontological Considerations on the Old Red Sandstone of Scot- 

 land," (160), in which they sought to prove that physical, strati- 

 graphical and palaeontological evidence all pointed to the marine 

 origin of the Old Red. In a few words their interpretation may be 

 summarized : in pre-Devonic time there was a large land-mass to the 

 northwest of Scotland which supplied the material for much of the 

 marine deposits during Cambric, Ordovicic and Siluric time. At the 

 end of the Siluric the sea began to transgress across Scotland and the 

 land-mass was at the same time depressed until by sinking and by 

 marine erosion the whole area disappeared beneath the sea and the 



