COPE I A 31 



geography gives important clues to systematic affinities. 



This policy has always had the support of the 

 University authorities and has not been modified in the 

 ten years since its adoption. During this time the 

 reptiles and amphibians have received considerable 

 attention, as they are groups selected for individual 

 study. They have been studied in some part of Mich- 

 igan every year, and also in various other places in 

 North America, Mexico and South America, with the 

 result that the fauna of the state is becoming fairly 

 well known and contributions have been made to knowl- 

 edge of the faunae of other regions and also it is hoped 

 to the general subjects of zoogeography and systematic 

 herpetology. 



Consistently with the general policy the field work 

 on reptiles and amphibians has been restricted to 

 intensive environmental studies. The method employed 

 is to select a general region which presents a geo- 

 graphical problem with apparently few complications 

 and not too large to be covered in the time available, 

 to locate the possible habitats, and to work each hab- 

 itat thoroly to obtain all of the inhabitants and to 

 determine as much as possible of the habitat relations. 



At the present time we are working on the mate- 

 rial obtained by expeditions sent to the Santa Marta 

 Mountains, Colombia, in 1913, to British Guiana in 

 1914, to the Davis Mountains, Texas, in 1914 and 1916, 

 and on preliminary collections frcm the Olympic Moun- 

 tains in Washington. To illustrate the nature of the 

 general problems attacked, perm't me to say that the 

 main object of the work in Colombia is to determine 

 the effects of isolation and of precipitous topography, 

 the problem attacked in Gu:'ana is the effect of the old 

 sand reefs on the fauna, the work in the Davis Moun- 

 tains is m the nature of an investigation of the prob- 

 lems of altitu^inal distribution in an arid region, and 

 in the Olympics it is the altitudinal distribution in a 

 wet region and the occurrence of forms with Asiatic 

 affinities upon which it is hoped to obtain information. 

 Although other exped : tons will be sent to each of the 

 regions mentioned, it is apparent that the field work 

 has yielded results from which conclusions bearing 

 on the problems stated may be drawn. 



That data on the relations between the animal at 

 all stages of ,- ts life history and its environment are 

 valuable, must, I believe, be evident to every one. The 



