66 



SEXUAL SELECTION. BIKDS. 



Part IL 



an extraordinary noise, the first " sharp note being not 

 " unHke the crack of a whip." ^® 



a 



d 



f 



Fig. 45. Secondary wing-feathers of Fip)-a delidosa (from Mr. Sclater, in Proc. Zool. Soc. 

 1860). The three upper feathers, a, b, c, from the male ; the three lower corresponding 

 feathers, d, e,f, from the female. 



o. and d. Fifth secondary wln^-feather of male and female, npper surface. b and e. 



Sixth secondixry, upper surface. c and/. Seventh secondary, lower surface. 



The diversity of the sounds, both vocal and instru- 

 mental, made by the males of many species during the 



56 Sclater, in ' Froc. Zool. Soc' 1860, p. 90, and in * Ibis,' vol. iv. 

 ^62, p. 175. Ako Salvia, in ' Ibis/ I860, p. 37. , 



1862 



