THE MALLARD. 487 



Though it never dives in search of .food, yet, when wing- 

 broken, the Brant will go one hundred yards at a stretch 

 under water, and is considered, in such circumstances, one 

 of the most difficult birds to kill. About the 15th or 20th 

 of May, they re-appear on their way north, but seldom stop 

 long, unless driven in by tempestuous weather." 



This bird nests in the most northern portions of the con- 

 tinent. The nest is similar to that of the Canada Goose. 

 The eggs are from five to eight in number : they are ovate 

 in form, sometimes nearly oval ; and of a yellowish-white 

 color, sometimes darkened into a creamy-buff. Their di- 

 mensions vary from 2.90 by 1.92 to 2.78 by 1.84 inch. 

 They are very smooth to the touch, and the shell is thin 

 and brittle. 



Sub-Family ANATIN^E. The River Ducks. 



The Anatince, or River Ducks, are easily known by their having the tarsi trans- 

 versely scutellate anteriorly, and the membrane or lobe of the hind toe narrow and 

 much restricted. The legs are longer than in Fuligulince, but shorter than in the 

 geese. 



All the North-American River Ducks agree in having the crissum black. In all, 

 excepting Querquedula, there is a tendency to waved lines on the feathers of the 

 flanks, most conspicuous in the Mallard, Gadwall, and Green-winged Teal. 



ANAS, LINN^JUS. 



Anas, LINNAEUS, Syst. Nat. (1735). (Type Anas toschas, L., Gray.) 

 Bill longer than the head or the foot, broad, depressed ; the edges parallel to near 

 the end, which is somewhat acute ; nail less than one-third the width of the bill ; 

 nostrils reaching to end of the basal two-fifths of the commissure ; feathers of fore- 

 head, chin, and cheeks, reaching about the same point; upper angle of bill about in 

 line with the lower; tail pointed, about two-fifths the wing. 



ANAS BOSCHAS. Linnmts. 

 The Mallard; Green-head. 



Anas boschas, Linnaeus. Syst. Nat., I. (1766) 205. Wils. Am. Orn., VIH. 

 1814) 112. Aud. Orn. Biog., III. (1835) 164. Ib., Birds Am., VI. (1843) 236. 



