234 The Bird 



The deep serrations, however, are but indentations in 

 the substance of the strong, narrow bill of the bird. 

 When once in this saw-like grasp, the most slippery fish 

 is helpless. The beak of the Shoveller Duck shows how 

 well Nature has provided for its wants. The beak is 

 arched and spatulate, while the sensitive epidermis is pro- 

 longed at the edges into a series of comb-like teeth, 

 analogous to the whalebone in the mouth of a whale. 

 Through this sieve the water is drained out, leaving 

 entangled the edible worms and insects. 



If we should elevate our Shoveller Duck, placing him 

 on long, slender legs and providing him with a corre- 

 spondingly long neck, he would indeed be in a predica- 

 ment, since only the tip of his beak could be brought 

 to bear in feeding. Now a flamingo is really a long- 

 legged duck, which feeds in much the same way as the 

 Shoveller, and the difficulty mentioned is overcome in 

 a most ingenious way. The mandibles are bent down- 

 ward, almost at right angles, so that, when the head 

 reaches the ground, not the tip but the whole inverted 

 bill is in a position to sift out food. To meet the reversed 

 condition, the lower mandible is deeply arched, instead 

 of the upper as in the Shoveller Duck. 



We are able to follow the probable evolution of such 

 remarkable beaks as those of the flamingo and skimmer 

 by observing the growth of this organ in any individual 

 from the time when the bird hatches from the egg until 

 it is full-grown. In the very young flamingo chick there 

 is no sign of the subsequent deflection, the mandible 

 being short, perfectly straight, and rather slender. As the 



