.RUNNING BIHDS. 445 



The Pigeons ( Columba\ like the preceding, have the beak vaulted, 

 the nostrils pierced in a membranous space, and covered with a carti- 

 laginous scale, that causes a considerable prominence at the base 

 of the beak. These birds fly we'll, the males attach themselves 

 strictly to a single female, with whom they live, roosting upon trees 

 or in the clefts of rocks, they lay few eggs, but at intervals 

 frequently repeated. The male assists the female in the work of 

 incubation. They feed their young brood with grain previously 

 softened in their own craw. 



ORDER OF RUNNING BIRDS. 

 CURSORES.* 



The principal characteristic of these birds consists 

 in the undeveloped condition of their wings, which 

 are quite disproportioned to the size of the body, and 

 completely incapable of flight. In some cases, these 

 rudimentary wings are but imperfectly furnished 

 with feathers, in others they are fully plumed, but 

 even then seem only to be used after the manner 

 of sails, to catch the wind and thus assist in run- 

 ning. They run with extraordinary swiftness, and 

 hence the name Cursores, or Runners, is applied to 

 them with great propriety. The living species 

 form two families, of one of which the Ostrich, 

 and of the other, the Apteryx, is the type. 



The Ostriches (Struthiomdse) are remarkable for the great size and 

 strength of their legs; the shortness of their wings is such that 

 they are quite unadapted for flight. 



The True Ostriches (Struthio}, however, still have their wings 

 covered witli loose and floating plumes of sufficient length to afford 

 them considerable assistance in running. Two species only are 

 known. The African Ostrich (Struthio camelus), and the American 

 Ostrich (Struthio fthced). 



The African Ostrich has only two toes upon each foot ; and 

 the outermost of the two, which is but half the length of the inner 

 one, is without a claw. These birds are very numerous in the sandy 

 desserts of Arabia and of the interior of Africa ; they attain the height 

 of seven or eight feet, live in large flocks, and lay eggs that weigh 

 nearly three pounds apiece : in intertropical regions these eggs are 

 simply buried in the sand, but beyond the tropics the female sits 



Cursor, a runner, from CUITO, to >'u)i. 



