NATATORES : PHALACROCORACID^ AND PLOTID^. 2?5 



the wing twenty-five, and the tail eighteen inches long ; 

 the prevailing color brownish black. In swiftness and 

 power of flight this bird is not surpassed by any other. 



PHALACROCORACIM:, OR CORMORANT FAMILY. This 

 Family comprises swimming birds which have the tip of 

 the bill much hooked, acute, and the nostrils not per- 

 ceptible. They are abundant on the coasts of all coun- 

 tries, and b'reed on rugged cliffs and on trees, and feed 

 upon fish, which they obtain with great expertness. 



The Genus Graculus comprises eight species. 



The Common Cormorant, G. carbo, Gray, of Labrador, 

 is thirty-seven inches long, and the wing fourteen inches ; 

 the color bluish black, gular sac yellow, with a broad 

 white band at the base. 



The Double-crested Cormorant, G. dilophus, Gray, of 

 the Atlantic and Pacific coasts ; the Florida Cormorant, 

 G. floridanus, Bonap., of the Southern States and of 

 the Mississippi ; the Mexican Cormorant, G. mexicanus, 

 Bonap. ; Brandt's Cormorant, G. penicillatus, Bonap. ; 

 and the Violet-Green Cormorant, G. violaceus. Gray, of 

 the Pacific coast, are additional species. 



PLOTID.E, OR DARTER FAMILY. This Family is char- 

 acterized by a long, straight bill, long wings and tail, and 

 short tarsi. 



The Genus Plotus comprises four species, one in Amer- 

 ica and three in the Old World. They inhabit the warm 

 regions, and are found in flocks. 



The Snake Bird, Darter, or Water Turkey, P. anhinga, 

 Linn., of the Southern coast of the United States, is 

 thirty-five inches long, and the wing fourteen inches ; the 

 general color greenish black. 



PILETONID,E, OR TROPIC-BIRD FAMILY. This Family 

 is characterized by a long bill, long wings, tail with cen- 

 tral feathers extremely elongated, tarsi short. 



The Genus Phceton is represented by the Yellow-billed 



