NATATORES. 445 



of South Africa and South America, especially at Terra del 

 Fuego, and in the solitary islands of the South Pacific. When 

 on land the Penguins stand bolt upright, and as they usually 

 stand on the shore in long lines, they are said to present a most 

 singular appearance. In the Auks (Alcidcz) the wings are better 

 developed than in the Penguins, and they contain true quill- 

 feathers; but they are still short as compared with the size of 

 the body, and are of more use as fins than for flight. The great 

 Auk or Gare-fowl (Alca impennis) is remarkable for being one 

 of the birds which appear to have become entirely extinct 

 within the human period, having been, in fact, destroyed by 

 man himself. It used to abound in the arctic regions, and 

 occasionally visited our own shores in the winter. The little 

 Auk (Mergulus alba) occurs still in abundance in the seas of 

 the arctic regions. Other well-known members of this group 

 are the Razor-bill, the Puffins (Fratercula arctica), and the Guil- 

 lemots (Uria). 



In the Divers (Colymbidat), comprising the true Divers and 

 the Grebes, the power of flight is pretty well developed, but 

 the bird still is much more active in the water, swimming or 

 diving, than on land. The Grebes are not uncommon in our 

 own country, and are largely killed for making muffs, collars, 

 and other articles of winter dress. They have the membrane 

 between the toes deeply incised. In the Divers proper the 

 front toes are completely united by a membrane. The Nor- 

 thern Diver or Loon (Colymbus glacialis) is a familiar example, 

 and is found on the coasts of high northern latitudes. 



Fam. 2. Longipennatce. This family of Natatores is charac- 

 terised by the well-developed wings, the pointed, sometimes 

 knife-like, sometimes hooked bill, and by never having the 

 hallux united with the anterior toes by a membrane. The fol- 

 lowing are the more important groups coming under this 

 head : 



a. Laridce, or Gulls and Terns, having powerful wings, a free 

 hinder toe, and the three anterior toes united by a membrane. 

 The Gulls form an exceedingly large and widely distributed 

 group of birds ; and the Terns or Sea-swallows are equally 

 beautiful, if not quite so common. 



b. Procellaridce, or Petrels, closely resembling the true Gulls, 

 but having no hinder toe, and having the upper mandible 

 strongly hooked. The smaller species of Petrel are well known 

 to all sailors under the name of Storm-birds and Mother 

 Carey's Chickens. The largest member of the group is the 

 gigantic Albatross (Diomedea exulans\ not uncommonly found 

 far from land in both the northern and southern oceans. The 



