THE PRINCIPAL BIRD GROUPS 57 



and general colouration. The wings are rounded 

 and short, suggestive of sedentary habits, whilst 

 the general actions somewhat resemble those 

 of the birds in the previous division. The eggs 

 of these birds are very remarkable, the surface 

 of the shell being so highly polished as to 

 resemble burnished metal or glass, and of 

 various striking colours, such as pale yellow, 

 green, blue, rich brown and orange. Another 

 interesting characteristic is that the male bird 

 performs the duty of incubation. But 

 little appears to be known respecting the 

 habits of these curious birds. Tinamous are 

 said by some observers to be somewhat stupid 

 birds, easily captured ; whilst their small brain 

 capacity seems to furnish another proof of 

 their comparatively low organisation. 



Our next group consists of those exceedingly 

 curious birds the Penguins, which form the 

 very distinct natural order Impennes, the 

 Sphenisciformes of some authorities. Perhaps 

 the most remarkable character of the Penguins 

 is their peculiar wings, which are so small and 

 flapper-like as to render the birds absolutely 

 flightless. These abortive wings, however, are 

 of great service to the birds in water, and in 

 some cases are used to assist their owner 



