126 BIRDS OF ILLINOIS. 



visitants. In the spring it was rare south of Minnesota, but 

 by the time it reached that State its numbers had been in-, 

 creased by recruits from the southeast, and it became almost 

 common." 



Subfamily ANATIN-ffi.— The Ducks. 

 Genus ANAS Linn^us. 



Anas LtHK. S. N. ed. 10, i, 1758, 122; ed. 12, i, 1766, 194. Type, by elimination, A. boschas 

 - Linn. 



Gbn. Chab. Hind toe without a membranous lobe, or "flap" ; bill not spatulate ; tail- 

 feathers li, narrow and pointed at the tip, but the middle pair notoonspiouously elongated, 

 the graduation amounting to less than one third its total length ; oulmen shorter than mid- 

 dle toe without tarsus. 



Having in the introduction to this work stated my intention 

 to follow the classification and nomenclature of the American 

 Ornithologists' Union's "Check List of North American Birds", 

 I find myself obliged to group several very strongly marked 

 and obviously distinct generic types under the generic name 

 Anas, these groups being admitted to merely subgeneric rank 

 in the scheme referred to. These so-called subgenera are char- 

 acterized as follows: 



A. Culmen longer tkan middle toe without olaw. 



a. Width of upper mandible near tip more than one third the oulmen, the upper and 

 lateral outUnes more or less convex for the terminal half. 



1. Anas. Wing more than 8.00 inches ; scapulars and tertials in adult males broad, and 

 without light-colored median stripes. 



2. Querquednla. Wing less than 8.00 inches ; scapulars and tertials in adult males lan- 

 ceolate, and marked with buffy or whitish median stripes. 



&. Width of upper mandible near tip less than one third ibe length of the culmen, the 

 upper and lateral outlines straight tor the terminal half. I (Wing less than 8.00 inches.) 



3. Nettion. 



B. Culmen shorter than middle toe without olaw. 



i. Chaulelasmus. Distance from anterior border of nostril to tip of upper ma,ndible 

 more than three times the distance from the same point to nearest loral feathers; 

 lamellsB fine and very numerous (more than 30 visible from the outside) ; tail- 

 feathers 16. 



6. Mareoa. Distance from anterior border of nostril to tip of upper mandible less 

 than three times the distance from the same point to neai-est loral feathers; lamel- 

 Ite coarser and less numerous (fewer than IB visible from the outside) ; tail-feathers 

 . 14, the tail much graduated. 



For the greater convenience of the reader, keys to the species 

 are given under tte separate subgeneric headings, which follow. 



