488 LAMELLIROSTRAL SWIMMERS — ANSERES. 



end, wliere the edge of the maxilla overhangs the mandible on each side ; behind this, 

 the fine lamella- completely exposed. Otherwise much like Querquedula (the wings colored 

 exactly the same), but larger. 



8. Aix. Bill much shorter than the head, deep througli the base, depressed terminally, the 



edges gently convex, and converging terminally ; nail verj'- large ; base of the maxilla 

 produced backward and upward into an elongated angle, extending on each side the fore- 

 head nearly half-way to the eye. Tail lengthened, composed of broad, rounded feathers, 

 Male with a full, elegant pendant crest of silky feathers. 

 B. Hind toe furnished with a membraneous lobe. 



a. Bill broad, depressed terminally ; tail short, the feathers moderately rigid, rounded at ends, 



and more than half concealed by the coverts (Fnlir/uke). 



9. Fuligula. Bill decidedly broadest at base, much depressed terminally, the vertical thick- 



ness just behind the nail being only about one fourth that at the base ; nail large and 

 very broad. Adult male with the head rufous, the pileum ornamented by a fuU and very 

 soft, bushy, rounded crest. 



10. Fulix. Bill aliout as long as the inner toe (with claw), the nail small and narrow. Head 

 ami neck black in adult males. 



11. iEythyia. Bill longer than inner toe, with claw. Head and neck reddish in adult males. 



b. Bill shorter than the head, rather compressed, the depth through the base considerably exceed- 



ing the width near the end ; terminal portion of the bill not at all depressed. Tail as in 

 FuUfjvlo'. (the central pair of rectrices much elongated in Harelda). (Clangula;.) 



12. Clangula. Bill much shorter than the head, compressed, and tapering, both laterally and 

 vertically, to the end, the nail small and narrow. Plumage chiefly black and white in the 

 male ; grayish and white, with brown head, in the female. 



13. Histrionicus. Bill as in Clangula, but the nail very large and broad, forming the end 

 of thi- bill, the rictus overhung by a small wrinkled meml>rane. Color plumbeous, with 

 white collar and other bands and markings, in the male ; dull grayish brown, with white 

 spots on head, in female. 



14. Harelda. Bill much shorter than the head, neaidy as broad as deep, the nail large and 

 broad, the feathering at the base forming a nearly straight line running obliquely from 

 the base of the culmen to the rictus.^ Middle pair of rectrices and posterior scapulars 

 mui'h elongated and lanceolate in the male. Colors variable. 



15. Eniconetta. Bill shorter than the head, much compressed, the edges of the maxilla 

 inllexed so as partly to inclose the mandible ; nail very large and broad, forming the end 

 of the bill, which is not at all " hooked." Male with the feathers of the lores and occiput 

 stiff and bristly, the tertials strongly falcate, the plumage beautifully A'^ariegated ; female 

 didl chestnut-brownish, variegated with black. 



16. Camptolsemus. Bill nearly as long as the head, the edges of the maxilla furnished 

 terminally with a thickened membraneous appendage, the base of the maxilla encased 

 with overlying skin, including the nostrils. Feathers of the cheeks stiffened and bristly. 

 Color black and white (head, neck, jugulum, and wings chiefly white, under parts, ring 

 round lower neck, and other parts black) in the male ; nearly uniform brownish-plumbeous 

 in the female. 



c. Bill shorter than the head, tapering both laterally and vertically toward the end ; the base 



of the maxilla continued in a lengthened angle or broad lobe on each side of the fore- 

 head, or else (in Arctonetla) densely feathered as far forward as the nostril. Males with 

 areas of stift', bristly, greenish feathers about the head, the tertials strongly falcate, the 

 plumage chiefly white and black, or plumbeous. Females brownish, barred with black 

 {SomaterioR). 



17. Arctonetta. Feathering at base of the maxilla extending as far forward as the nostril, 

 and forming a contiiuious obli([ue line from the culmen to the rictus ; feathers of the 

 lores dense and velvety ; eyes surrounded by a dense roundish "cushion" of short, soft, 

 velvety feathers. 



^ In some specimens there is a distinct feathered angle projecting toward tlie nostril, the bare skin of 

 the bill forming an obtusie angle above it. 



