22 Zoology of Colorado 



He represents what in zoology we call a subspecies; a group of 

 individuals with evident distinguishing characters, but inter- 

 grading with the other groups of the species. This "intergra- 

 dation" is not due to the existence of a series of tribes perfectly 

 connecting the great divisions of mankind, but to the fact that 

 interracial marriages are fertile and produce fertile offspring. 

 There is, as we put it, no physiological barrier between the sub- 

 species. It is thus out of the question, as much on biological as 

 on sentimental or religious grounds, to recognize more than one 

 species of existing man. As to social and psychological differ- 

 ences, they are still subject to dispute. Descriptive sociology 

 and psychology may reveal numerous marked racial character- 

 istics, but events have shown that these may often be modified 

 within a single generation. What are the biological, hereditary, 

 irreducible differences, we do not clearly know. We can no longer 

 assent to the naive and simple classification which describes 

 Europeans as governed by law, Americans (Indians) as regulated 

 by customs, Asiatics governed by opinion, and Africans by 

 caprice ! 



The nearest relatives of man now living in Colorado are the 

 bats (Order Chiroptera) and insectivores (Order Insectivora). 

 The bats are quite numerous, about sixteen different forms 

 having been reported. Since the publication of Warren's Mam- 

 mals of Colorado (1910), Miller has denned a new form of the 

 little brown bat, calling it Myotis longicrus interior. It has been 

 obtained at Grand Junction and Coventry in our State, and is 

 paler than the typical M. longicrus, being tawny-olive above, 

 slightly paler below. The original and therefore typical M. 

 longicrus was from Puget Sound, a region of heavy rainfall where 

 animals and birds tend to be of dusky hue. The generally pallid 

 character of bats in the arid region is indicated in the names of 

 some of our Colorado species. Thus we have Antrozous pallidus, 

 the pale bat, described from El Paso, Texas, but extending into 

 southern Colorado. Then there is Eptesicus pallidus, better 

 called Eptesicus fuscus pallidus, described by Young from a 

 specimen collected at Boulder. It does not appear quite certain 

 that this is more than a peculiar individual, but it is in line with 

 the general tendency mentioned. Corynorhinus macrotis pal- 

 lescens, the pale big-eared bat, was first found in Arizona, but it 



