Coloration of the Mouths and Eggs of Birds. 285 



Bulbul in this homoeocliromatic combination is at first 

 sight interesting, but it would be unsafe to suggest mimicry 

 until more is known of the mouths of Bulbuls and 

 Weavers generally, where geographically associated and 

 where not. I quote from my original note on the bird 

 whose mouth is figured (Pi." VII. fig. 15) :—'^ 18.3.13. 

 Pycnonotus layardi. Barely beginning to feather. Three 

 in nest, all same. Mouth-likeness to Hyph.jamesoni extra- 

 ordinary, and same wobble of head. Has a rather Weaver- 

 like food-note too, 'tsip, tsee,' as well as a more Bulbul- 



like tone Sometimes brighter than at others, 



even nearly carmine." I found, in fact, that when I opened 

 the mouth myself it was dull pale brownish in coloration, 

 the bright colour that makes it so like the Weaver's mouth 

 being, in this case, evidently due, not to pigment, but to a 

 rush of blood to the mouth under the stimulus of eagerness. 

 So much at present for resemblances. 



Highly distinctive mouths were those of Colius siriatus 

 minor (fig. 17) — a yellow "lantern" of a fleshy tongue in 

 a black mouth — and, yet more distinctive, Centi-opus Lurchelli 

 (fig. 21) — tongue crimson and black, with white papillse (the 

 latter not so conspicuously displayed as in the figure) in an 

 otherwise unpigmented mouth, and with its own terminal 

 third unpigmented. The young birds of Centropus had " a 

 remarkable wheezy food-call, uttered continuously when 

 anyone was present, the tongue being pushed rapidly back 

 and forth meantime with mouth wide open and directed 

 straight at the approacher.'' One of these nestlings that I 

 offered to a lemur and a cat was apparently much disliked 

 by them. A youngish Trachyphonus cafer (fig. 44) that I 

 shot still showed strong traces of what seemed to have been a 

 similarly coloured tongue less strongly, as did an Indicator, 

 a matter probably of affinity. Yet another rather striking 

 mouth was that of a nestling Macronyx croceus, which I have 

 also figured (PI. VII. fig. 19). I do not know the food-status 

 of this nestling. The eggs were much disliked by my rat, 

 while the adult birds were placed quite high in the scale of 

 palatability, though not amongst the pleasautcst, by my cat 



