BIKDS 



137 



but to a lower degree. I cannot attempt to show how these 

 degrees of dimorphism correspond to the differentiation of 

 habits in the male and female, but shall content myself by 

 referring to the celebrated species called the Quezal, which is 

 the culminating example of the condition last mentioned. 

 The Quezal, Pharomacrus mocinno, lives in the forests of 

 Guatemala. The body is no larger than that of a turtle dove. 

 The special adornments of the male are a rounded crest on 

 the head, enlarged scapulars or shoulder feathers, and much 

 elongated tail coverts, corresponding to those of the peacock. 

 These hypertrophied feathers and the upper part of the body 

 generally are of a beautiful iridescent green colour, while the 

 under parts are of a gorgeous crimson. The female is also 

 green above, but her crest is less developed, and her tail 

 coverts are not elongated beyond the true tail. 



Mr. 0. Salvin (Ibis, 1861, pp. 66 and 138) gives reasons 

 for believing that the male Quezal takes no part in incuba- 

 tion, and describes the behaviour of the living male bird 

 under his own observation for a few minutes in its natural 

 condition. The bird sat on a bough with its tail hanging 

 down, and this was occasionally jerked open and closed again, 

 which caused the long tail coverts to vibrate gracefully. 

 Here at any rate is the agitation of the specialised feathers, 

 which I contend to be universal, but we may be very con- 

 fident that a great deal more agitation and erection of all the 

 special feathers takes place when the male bird is in active 

 courtship, although he is commonly found in company with 

 a single female. 



Paradiseidce. The Paradiseidse are included among the 

 Passerine birds, Dr. Gadow's Order Passeriformes, and are 

 considered to be undoubtedly allied to the Corvidse, to our 

 common Rook and Jackdaw, notwithstanding the sombre 

 plumage of the latter. 



In the Birds of Paradise, the males are distinguished from 



