38 Birds of Colorado 



Mottled Duck. Anas fulvigula maculosa. 



A.O.U. Checklist no 134a — Colorado Records — Ridgway 73, pp. 177, 

 188 {Ana3 obsciira) ; Morrison 89, p. 148 : Cooke 97, pp. 53, 156, 194 ; 

 Felger 09, p. 280 ; 10, p. 451. 



Description. — Resembling a dark-coloured female Mallard ; head 

 and neck buiTy, finely streaked with dusky ; chin and throat Isabella - 

 coloiu- unmarked ; under -parts mottled about equally with dusky 

 and light brown ; feathers of the breast and back with brown centres 

 and margins ; speculum greenish purple framed in black, the feathers 

 narrowly tipped with white ; iris dark brown, bill greenish with a black 

 spot at the base of the lower edge of the upper mandible ; legs reddish- 

 orange. Wing 10-0; tarsus 1-75; culmen 2-25. 



The sexes are alike, except that the female has no black spot on the 

 mandible. 



Distribution. — Breeding in Texas and probably north to Kansas 

 and Colorado. 



A Duck identified formerly as the Dusky or Black Duck of the 

 Atlantic coast, has been recorded on several occasions from Colorado. 

 It was first noticed by Ridgway on the authority of Aiken. Thome 

 took it at Fort Lyon (Morrison) and Osbum on the Big Thompson 

 near Loveland, March 15th, 1889. Cooke in his second supplement 

 (p. 194) considered that these Ducks should be referred to the present 

 subspecies. 



In the Natural History Museum at Denver there is a Duck taken 

 November 6th, 1907, near Loveland, by Mr. Blaney ; it is mounted, 

 and the bill has been coloured so that it is impossible to make out the 

 spot on the mandible, but the throat is clearly plain and unstreaked, 

 and I have httle doubt that it should be referred to this subspecies, 

 which may therefore be considered a straggler to Colorado. Felger 

 (09) gives several additional records from the neighbourhood of Denver, 

 and in a recently published note (10) considers that Cooke is in error, 

 and that these Colorado Ducks should be referred to A. rvbripes. I 

 have myself carefully examined the example mounted in Denver, 

 and am inclined to support Cooke in his determination. 



Genus CHAULELASMUS. 



Closely resembling Anas, with a tail of sixteen feathers, but wing 

 speculiun white, and in the male the greater coverts black, the 

 middle coverts chestnut. 



One nearly cosmopolitan species. 



Gad wall. Chaulelasmus streperus. 



A.O.U. Checklist no 135— Colorado Records— Allen 72, p. 159 ; 

 Aiken 72, p. 210 ; Henshaw 75, p. 474 ; Drew 81, p. 142 ; 85, p. 18 ; 



