x OSTEOLOGIA AVIUM. 



feet ; some few birds, however, are found, in the first family, Anatidee, which feed upon 

 land, chiefly on the seeds of grasses, having the webs not extending much more than 

 half the length of the toes, or with the anterior edge much scolloped out. 



The Colymbidse and Alcidae may be considered as possessing the greatest powers of 

 swimming and diving. In one genus (Spheniscus), the wings, instead of being useful for 

 flight, are converted into a sort of fin, the bones composing the wing being much 

 flattened ; the hinder extremities are very muscular ; and the legs are placed far back- 

 wards. In some of the Pelecanidse and Laridse we find great power of wing developed 

 at the expense of the diving powers, which are limited and governed by that of the 

 wing. Their mode of taking prey is by soaring high into the air, closing the wings, 

 and making a hawk-like swoop upon fish near the surface. 



