284 THE BIRDS 



the two families differ in habits and habitat, they have in common 

 certain peculiarities of structure. The Divers are marine birds, and 

 unless driven inland by stress of weather are rarely seen on the 

 quieter waters, except in the breeding season, when they ascend 

 the rivers in pairs and nest on the moors. The Black-throated 

 Diver and the Red-throated Diver both breed on small islands on 

 the lakes or little pools upon the moors in Scotland. The Great 

 Northern Diver breeds in Iceland, Greenland and in the fur 

 countries. On land these birds appear somewhat ungainly, as they 

 walk with difficulty owing to the legs being set very far back, 

 but in the water they are agile and graceful, being expert swimmers 

 and divers. In Scotland the Red-throated Diver is called the 

 " Rain-goose," as before storms it frequently utters its loud and 

 rather melancholy cry. 



Although a few Grebes frequent the seas in certain periods 

 of the year, they are, as a whole, fresh-water birds. The best- 

 known British species is the Little Grebe, or Dabchick (Podicipes 

 ftuviatilis), that frequents the rivers and meres. It is a shy bird, 

 and when alarmed instantly dives under water. The Great Crested 

 Grebe (P. cristatus) is also seen in British waters ; it frequents 

 reed-covered pools in the summer months, but in the winter it 

 departs to the sea. 



The Albatrosses, Fulmers, Shearwaters and Petrels are grouped 

 together under the name Tubinares, or tube-nosed birds, from the 

 fact that in this order the nostrils are produced into tubes which 

 are directed forward on the beak. They are pelagic birds with 

 wonderful powers of flight, chiefly frequenting the Southern Hemi- 

 sphere, although representatives are found in the seas in nearly 

 all parts of the world. In size these birds vary very greatly; the 

 Wandering Albatross, the largest species, often measures twelve 

 feet from tip to tip of its outstretched wings a wider spread of 

 wing than that of any other living bird while the Storm-Petrel, 

 the smallest of the Tubinares, is not much larger than a swallow.- 



The Albatross family (Diomedeince] have their curious nasal 

 tubes placed far apart on either side of the beak, and they are 

 also distinguished by the extreme length and narrowness of the 

 wings. The Wanderer (Diomedea exulans), the most notable of 

 the Albatrosses, in spite of its large size, is wonderfully light, 

 weighing no more than sixteen or seventeen pounds, and is capable 



