I 20 The Bird 



the nests consisted entirely of half-digested seaweed, but 

 it has been proved that this is not the case. The homes 

 of these birds are the ''edible birds'-nests " held in such 

 esteem by Chinese gour7nands. 



The Tongue 



If we had a long series of birds' tongues before us, 

 we would be surprised at the great variety of shapes and 

 sizes. Observing the good-sized tongues of sparrows and 

 other small birds, we would turn to a pelican expecting 

 to see an enormous affair to correspond with the huge bill 

 of that bird. On the contrary we will find a tiny incon- 

 spicuous flap not larger round than a toothpick. This 

 reminds us of the condition of the tongue in some fishes, 

 where it is a very simple structure indeed. The king- 

 fisher also has a small tongue, and the same is true of 

 many other fish-eating birds, such as pelicans and most 

 of those which feed on large insects. The reason is ob- 

 vious. The food, which is swallowed whole, is of such 

 large size that a tongue of even moderate proportions 

 would be only in the way. 



The tongues of many birds are provided with oblique 

 series of teeth, either soft and fleshy or horn}^ in struc- 

 ture, which })oint backward toward the gullet and must 

 be of great help to the bird in guiding and swallowing its 

 food. These teeth are especially abundant around the 

 glottis, or opening to the windpipe, guarding it from 

 chafing or from the chance of food choking it up. 



In ducks and geese we find tongues large and of com- 

 plicated appearance. The edges are often toothed or 



