THE ALLIES OF THE PIGEON : AVES 



387 



small or medium size. Among them are included all our 

 well-known songsters. The nesting-habits are various, but a 



FIG. 205. Nest of Catbird 



great number build complicated and often beautiful nests 

 (Fig. 205) in which to rear their young. The young when 

 hatched are 

 always in a 

 helpless condi- 

 tion, requiring 

 the care of the 

 parent for a 

 time (compare 

 Figs. 206 and 

 199). The sexes 

 may be alike, or 

 the male may 



FIG. 206. Youns; of Catbird 



be specially 



ornamented. 



The bright colors of the male are generally believed to be 



due to sexual selection, and his ability to sing is accounted 



