ANATIDA — FULIGULINZ: SEA DUCKS. 699 
in consequence of which the gait is still more awkward and constrained than the ‘* waddle” of 
ordinary ducks; but swimming powers are enhanced, and diving is facilitated. A large 
number of the species are exclusively maritime, but this is no more the case with all of them, 
than is the reverse with the river ducks. These birds feed more upon mollusks and other 
animal snbstances (not, however, upon fish, like the mergansers) than the river ducks do, and 
their flesh, as a rule, is coarser, if not entirely too rank to be eaten; there are, however, signal 
exceptions to this, as in the case of the canvas-back. The sexes are unlike, as among the 
Anatine ; and besides the difference in color, the Q is often distinguished by the absence or 
slight development of certain tuberosities of the bill that the ¢ of several species, as of scoters 
and eiders, possesses. A large majority of the species inhabit the Northern Hemisphere; there 
are some forty in all, exhibiting a good deal of diversity in minor details, really requiring 
recognition of many genera. Among notable exotics, we have the soft-billed Hymenolemus 
malacorhynchus of New Zealand, and the short-winged Micropterus cinereus of South America, 
both related to our genus Camptolemus ; there are but few others. The genus Hrismatura is 
the type of a sinall group remarkable for the character of the tail, as described beyond, and 
sometimes considered as a subfainily apart. Biziwra lobata of Australia, with a fleshy appen- 
dage under the bill, the African Thalassornis leuconota, the Nesonetta aucklandica, and several 
species of Hrismatura and Nomonyx, compose this group. 
Analysis of Genera and Subgenera. 
Tail-feathers rigid, narrow, linear, exposed to their bases by shortness of coverts. 
Nail of bill ordinary . . Bid a. is Weeds Lg ROMO Cee cde 
Nail of bill narrow above, eae acta ceieaiedl cman tip ‘of pill 5) e sl we Ce Lismatura 298 
Tail-feathers and their coverts ordinary (central pair very long, however, in Hare/da #4). 
Bill variously gibbous, or appendaged, or featliered beyond nostrils. 
Bill gibbous at base, then broad, depressed, with large fused nail, without frontal processes. 
Gibbosity of bill superior, circumscribed; feathers not projected on culmen. 
Tail 16-feathered. @: Color entirely black (GEDEM1A) : 2, aes 
Gibbosity of bill superior, circumscribed ; feathers projected on een “Tail 14- 
feathered. of: Color black or dark, with white wing-patch (MELANETTA) . 
Gibbosity lateral as well as superior; feathers projected on culmen. 
Tail 14-feathered. gf: Color black, with white head-patches (PELIONETTA) 
Bill gibbous at base, with large frontal processes. 
Frontal processes in line with culmen (SOMATERIA proper) 
Frontal processes bulging out of line with culmen(ERIONETTA). . .. 
Bill not gibbous, but feathered on culmen beyond nostrils (ARCTONETTA) 
Bill not gibbous, but appendaged with leathery expansion of side of upper Pian otiisiet 
cheeks not bristly (HENICONETTA) 
Edemia 297 
Somateria 296 
Bill not gibbous, but appendaged with a lobe at base of commissure. . . . . . . Histrionicus 295 
Bill not gibbous, but appendaged with a leathery expansion of side of upper mandible; cheeks 
Disb) aan ee eta ee ees iehe Se We estiecd for a alae. Gis, vom fey ic, <9 6,’ CO PLOLCE MNS 208 
Bill ordinary. 
Nail of bill large, fused. Tail (of #)aboutaslongaswing ........-. . + Harelda 298 
Nail of bill narrow, distinct. Tail of ordinary length and shape. 
Bill shorter than head, high at base. Head of ¢ puffy or crested, iridescent, with 
white patches; crissum white; colors black and white,in masses. . ... - Clangula 
¢, white spot before eye (CLANGULA proper) 
¢, white patch behind eye (BUCEPHALA) . . 
Bill about as long as head. Head of # black, red, or ee vaikhiont See cris- 
sum dark. . . 4 Sue ea eS at cee pa eee 
Bill dusky. Head of a dhakey reddish ‘(Action a) Uren elt) tes is | PRG UL ZO 
Bill bluish or blackish. Head of # black or red. (FULIX) . .... - 
Bill red. Head red, crested (European). (FULIGULA proper) . 
Norte. — See further analyses of the subgenera (some of which are of generic value) under heads of @demia, 
Somateria, and Fuligula. 
FULIGULA. (Lat. fuligula or fulicula, dim. of fulix or fulica, a coot; fuligo, soot.) 
BLACK-HEAD and Rep-HEAD DucKs. Scaups and Pocuarps. Bill ordinary, without 
special gibbosity or peculiar outline of feathers at base, only in one species (F’. vallisneria) 
