A SMALL PROBLEM. 



213 



birds present, of all ages and sexes, we should say there 

 were not ten per cent, which displayed this singular 

 pouch. The few red cocks which I observed incubating, 

 were very shy, and I only once succeeded in taking a 

 snap-shot of one. 



At this height, where we first came across any nests, 

 the Trades were blowing fresh and strong, and to see these 

 old birds, poised and balanced, against the stiff breeze, 

 thirty feet or so above our heads, was a sight we shall not 

 soon forget. The translucent sac, vivid scarlet or blood 

 red in colour, is about the size of a large double fist, but 

 more elongated in shape. Its neck is rather long and 

 constricted, which causes it to wobble about in the wind 

 in a strange and somewhat ridiculous way. It reminded 

 one, for all the world, of a child's gaily coloured toy 

 balloon. What purpose it serves it is rather difficult to 

 say. It is capable of being inflated or deflated at the 

 pleasure of the bird ; but it can hardly be intended as an 

 adornment to fascinate the hen, because by far the larger 

 proportion of young males already mated were without 

 it. Nor would it seem necessary as an increased aid to 

 buoyancy, for between the entire skin of the bird and the 

 deeper tissues is a mass of air cells, mere spaces in the 

 loose connective tissue, which can be filled with air at the 

 pleasure of the bird. Besides which, why should it 

 be necessary for the cock bird to be more buoyant than 

 the hen ? 



Old hens are to be distinguished by having the entire 

 head and neck, as well as the under-parts of the body, 

 white. Younger hens, which were breeding, can hardly 

 be distinguished from their young mates. Both have 

 black heads with white throats and breasts. 



Briefly tabulated, we noticed the following varieties 

 and stages of plumage : (1) Old males , with red gular 

 sacs — rest of plumage black, with a beautiful glossy, 

 greenish-purple sheen. Infinitely the rarest. 



(2) Old females. Head, nape, throat and under-parts 

 white. Rest of plumage black, with the same gloss as 



