132 VERTEBRATES: BIRDS. 



of reddish-brown, and narrow irregular transverse lines 

 of the same color, and of black, on the abdomen ; -the 

 tibiae and tarsi bright ferruginous, with transverse lines 

 of black. 



The Genus Asturina comprises A. nitida, Bonap., of 

 Northern Mexico and South America. 



The Genus Nauclerus is characterized by very long 

 and pointed wings, and very long and forked tail, and by 

 short bill, tarsi, and toes. Three species are known, two 

 American and one African. 



The Swallow-tailed Hawk, N. fiircatus, Vigors, of the 

 Eastern United States to the Mississippi and northward 

 to Pennsylvania and Wisconsin, is twenty -three to twenty- 

 five inches long, the wing sixteen to seventeen and a 

 half inches ; the head and neck and entire under parts 

 white ; the back, wings, and tail black, with a metallic 

 lustre. The flight of this hawk is peculiarly graceful, and 

 its motions very rapid. It glides along with gentle flap- 

 pings, rises in circles, describes deep curves, and performs 

 all kinds of evolutions in a manner that never fails to 

 interest the beholder. It never attacks birds, but preys 

 upon insects and reptiles, and always devours its prey 

 while on the wing. 



The Genus Elamts has the wings long and pointed, 

 tail moderate and emarginate, but not forked. 



The White-tailed Hawk, E. leucurus, Bonap., of the 

 Southern and Western States and of South America, is 

 fifteen to seventeen inches long ; the head and tail and 

 entire under parts white ; the upper parts light cinereous, 

 lesser wing coverts glossy black, inferior wing coverts 

 white with a smaller patch of black. 



The Genus Ictinia is characterized by a short and 

 compact body, wings long and pointed, tail short and 

 emarginated, and the tip of the bill emarginated. 



The Mississippi Kite, /. mississippiensis, Gray, of the 



