280 FEET OF THE GBEBES. 



than the mere form of the lobed toes, is the reason of 

 its being so bad a walker. 



But the feet are admirably fitted for aquatic motion. 

 They turn their thin edges nearly in the direction of 

 the resistance when they are drawn forward, but they 

 strike back with the full breadth of their webs, and 

 they can turn on the joints so as to give the stroke in 

 a variety of directions, and thus impel the body upon 

 any course which may be necessary to the bird in 

 following its prey in the water. The wings also come 

 into action in swimming, though more as points of 

 support, against which the legs act, than as propelling 

 organs. But the birds are altogether excellent swim- 

 mers, or rather coursers through the water with great 

 speed. They do not dabble like ducks, but plunge 

 freely into the water, and dash along, not by alternate 

 strokes of the feet, as in a common walking motion, 

 bnt by striking with both at once, as a frog does. It 

 is to enable them to perform this motion that the 

 wings are brought into action as well as the feet ; and 

 the same kind of motion could not be performed, and 

 the intended course kept, without the wings. This 

 is, in part at least, the reason why those aquatic birds, 

 which are incapable of flight, have the wings, though 

 destitute of flying feathers, much more produced and 

 capable of motion than those of the running birds 

 upon land. The different styles of motion through 

 the water, whether on the surface or below it, can, 

 however, be more briefly, as well as clearly explained, 

 when we come to consider the habits of those birds 

 which have entire webs on the feet, and range the 

 water in places where they are not liable to interrup- 

 tion from the stems of plants. 



What may be considered as the normal swimming 

 foot consists of three toes directed to the front, and 



