126 BmDS OF rLLINOIS. 



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 ANATINiE.— The Ducks. 

 Genus ANAS Linn/EUS. 



Anas Linn. S. N. ed. 10. i. 1758, 122; ed. 12, i, 1766, 194. Typo, by elimination, A. bosctias 

 Linn. 



Gen. Char. Hind too without a membranous lobe, or "flap" ; bill not spatulate ; tail- 

 feathers 14, narrow and pointed at the tip, but the middle pairnot conspicuously elongated, 

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

 dle too 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 strongl}' 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 than middle toe without claw. 



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

 lateral outlines more or less convex for the terminal half. 



1. Anas. Wing more than S.OO inches; scapulars and tortials in adult males broad, and 

 without light-colored median stripes. 



2. Querquedola. Wing less than 8.00 inches : scapulars and tertials in adult males lan- 

 ceolate, and marked with buffy or whitish median stripes. 



h. Width of upper mandible near tip less than one third the length of the culmen. the 

 upper and lateral outUnes straight for the terminal half. I (Wing less than S.Oit inches,) 



3. Nettion. 



B. Culmen shorter than middle toe without claw. 



4. Chaulelasmus. Distance from anterior border of nostril to tip of upper mandible 

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

 lamella; flue and very numerous (more than :10 visible from the outside); tail- 

 feathers IC. 



5. Mareoa. Distance from .anteiior border of nostril to tip of upper mandible less 

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

 hv coarser and less numerous (fewer than 15 \isiblo from the outside) ; tail-fcathcre 

 14, the tail much graduated. 



Foi' the greater convenience of the reader, keys to the species 

 are given under the separate subgeneric headings, which follow. 



