PLOTIDH, DARTERS. —GEN. 276. 305 
violaceus that floridanus does to dilophus. Pacific Coast, N. A.— Pelecanus 
violaceus GM., 1, 575? Graculus violaceus Lawn. in Bp., 881; ScHLEGEL, 
l.c. 17; Urile bicristatus Bonap., Consp. Av. ii, 175 (nee Pall.) ; Phala- 
crocorax resplendens AuD., vi, 430, pl. 419; G. bairdit Coor., Proc. Phila. 
cr eSGD seo. OM EonIOr,, pl. 49.00 9. 2) 2... VIOUACEUS. 
Family PLOTIDA:. Darters. 
Bill about twice as long as the head, straight, slender, very acute, paragnathous, 
the tomia with fine serratures. Gular sac moderate, naked. Nostrils minute, entirely 
obliterated in the adult. Wings moderate, the 3d quill longest. Tail rather long, 
stiff, broad and fan-shaped, of 12 feathers widening towards the end, the outer web 
of the middle pair curiously crimped (in our species). 
There is an occipital style, as in cormorants, but it is very small. The digestive 
system shows a remarkable feature; instead of the lower part of the cesophagus 
being occupied by the proventricular glands, these are placed in a small distinct 
sac on the side of the gullet. As in other Stegunopodes, the gizzard develops a 
special pyloric cavity. There are no proper coca, but there is a small rounded 
termination of the rectum (Audubon). 
The darters are birds of singular appearance, somewhat like a cormorant but 
much more slightly built, and with exceedingly long slender neck and small con- 
stricted head that seems to taper directly into the bill. As in the cormorants, there 
are long slender feathers on the neck; the sexes are commonly distinguishable, but 
the 9 is said sometimes to resemble the ¢. Other changes of plumage appear to be 
considerable, but not well made out. The feet are short, and placed rather far 
back, but the birds perch with ease. Unlike most of the order, they are not mari- 
time, shunning the seacoast, dwelling in the most impenetrable swamps of warm 
countries. They fly swiftly, and dive with amazing ease and celerity. They are 
timid and vigilant birds; when alarmed they drop from their perch into the water 
below, noiselessly and with scarcely a ripple of the surface, and swim beneath the 
surface to a safe distance before reappearing. When surprised on the water, they 
have the curious habit of sinking quietly backward, like grebes; and they often 
swim with the body submerged, only the head and neck in sight, looking like some 
strange kind of water serpent. They feed on fish, which they do not dart down 
upon, but dive for and pursue under water like cormorants and loons. The eggs 
are three or four, pale bluish, with white chalky incrustation. There are only three 
or four species: the African P. levaillantii; the P. melanogaster of Southern Asia, 
with the Australian P. nova-hollandic, if distinct from the last ; with the following : 
276. Genus PLOTUS Linnezus. 
Darter. Anhinga. Snake-bird. Water-turkey. Glossy greenish-black ; 
a broad gray wing-band formed by most of the coverts ; lower neck behind 
and scapulars ed with grayish-white; tertiaries striped with silvery 
ash; tail pale-tipped; filamentous feathers of neck purplish-ash; ¢ with 
parts of the head, neck and back brown, the jugulum and breast fawn-color 
sharply margined with rich brown. Length about 56; extent nearly 4; wing 
14; tail 11; bill 34; tarsus 14. S. Atlantic and Gulf States, common; in 
summer to North ence (Audubon), and up the Mississippi to S. Illinois 
KEY TO N. A. BIRDS. 39 
