Vol. XXXVII 



1919 



Bergtold, The Crow in Colorado. 201 



Crows seen by Warren (17 and 20) in other parts of the State 

 are given as subspecies brachyrhynchos, but again named on regional 

 grounds only. 



From the foregoing it appears that the Crows of Colorado were 

 listed, principally as Corvus americanus up to the acceptance of 

 subspecies hesperis in the A. O. U. 'Check-List,' and since then 

 variously listed as Corvus brachyrhynchos, Corvus brachyrhynchos 

 brachyrhynchos, or Corvus brachyrhynchos hesperis, but, to repeat, 

 so far as I can learn, in no instance have any of the last two kinds 

 of records been made on skin determinations. This statement is 

 based on a study of the published records, and on a considerable 

 relevant correspondence with my associates throughout the State; 

 if I err the statement is open and subject to correction. 



The western third of Colorado lies on the Pacific slope, and the 

 eastern two-thirds on the Atlantic and on both of these slopes the 

 Crow has been detected, and variously recorded as to subspecies. 

 The A. O. U. 'Check-List' does not speak of hesperis actually 

 extending eastward to the Rocky Mountains, but Mr. Ridgway, 

 in a recent communication said to me " 1 feel quite sure that any 

 Crow found west of the Divide in Colorado would be C. b. hesperis. 

 On the other hand, those found on the eastern side would almost 

 certainly be C. b. brachyrhynchos." 



1 am fortunate, not only in having material in my own collec- 

 tion, which substantiates Ridgway 's belief, but in also having had 

 access, thanks to my obliging friends, to specimens and data which 

 also show that his belief is essentially correct. 



1 have been able to study fourteen Crow skins from the eastern 

 side of the Rockies in Colorado, six males and eight females; of 

 the males three are typical brachyrhynchos, two are clearly hesperis, 

 and the last is mainly brachyrhynchos, but with weaker bill and 

 tarsus than is ordinarily found with that subspecies. It is of 

 interest to note that this last specimen was taken in Weld County 

 close to the locality whence came the two previously mentioned 

 hesperis skins. It is much more difficult to allocate the females of 

 this group of skins; however four are more typically subspecies 

 brachyrhynchos than is another female in my collection which 1 

 collected many years ago in New York, and another female is also 

 of this subspecies, but with a weak bill, while the remaining three 



