/./• QUELCH. 125 



of pounded corn or maize, produce eventually yellow- 

 colored birds. In the former case, the change is evidently 

 a chemical one — probably of reduction ; while in the latter, 

 it would seem to be of the nature of the elimination or sub- 

 stitution of certain elements of the normal coloring, de- 

 pendent on certain normal kinds of food material. 



The peculiarity of form in many different organs of our 

 birds is also noticeable. Thus the elongated and peculiarly 

 curved beak of Xiphorhynchus the boat-bill of Ca?icroma, 

 the scissors-bill of Rhyfichops, the swollen tubular bill of the 

 Toucans and Jabiru {Rhamphastos and Mycteria), and the 

 keel-bill of Crotophaga, excite wonder, as much so as the 

 great gapes of the Calf-bird {Gymnocephaliis calvus) and the 

 Giant Night-Jar {Nyctibius grandis). The elongated tails 

 of the Macaws (Ara), the forked tails of Milvidus, and 

 the plucked central elongated tail-feathers of Momotus, may 

 also be mentioned, as well as the peculiarities in beak, crests, 

 puffs and tails of so many genera of Humming- birds, such 

 as Topaza, Discura, Lophornis and others. 



One of the most curious structural features in any of our 

 birds is that found in the appendages of the genus Chasmo- 

 rhynchus. As narrated elsewhere (see " Timehri," June, 

 1892, Georgetown, British Guiana), I have recently been 

 able to ascertain that the intermaxillary caruncle in C. albus, 

 has no influence on the notes of the bird, and cannot be 

 erected in the peculiar vertical manner shown in all the 

 former illustrations of the bird. This organ is extremely 

 extensile, and at the time of utterance of its notes by the 

 bird, hangs down to as much as five or six inches ; but it 

 never becomes inflated with air, neither when the head of 

 the bird makes its horizontal movement for the anvil-like 

 ring of " Kong-Kaay," nor during its vertically upward 

 movement for the bell-like sound " Do-rong." 



Brilliant as so many of our birds are, it must be confessed 

 that song, or sweetness of sound, goes not with their beauty 

 — at any rate, not with the most beautiful. The Macaws, 



