292 VERTEBRATE ZOOLOGY 



shafts; they overlap one another in the most perfect fashion so as to 

 shed effectively all water from the skin. Certain burrowing species of 

 the Falkland Islands differ rather sharply from the others, in that 

 they lay their eggs in rather shallow burrows. The penguins are con- 

 sidered to be so radically different in structure from both flying birds 

 and ratite birds that they might well be placed in a separate division 

 coordinate in rank with the Ratitse and the Carinatse. 



THE LOONS AND GREBES (COLYMBIFORMES) 



This archaic and quite isolated group of diving birds is placed 

 first among the modern flying birds because they possess a more 

 generalized structure than any other. The loon or great northern 

 diver (Fig. 156, A), is the example of the order most familiar to dwell- 

 ers in the Northern States. Its weird, laughing cry is one of the out- 

 standing features of our northern woodland life. The ability of the 

 loon to dodge a bullet by diving is proverbial, even if not true. The 

 coloration of this striking bird is a study in contrasting blacks and 

 whites, with a checkered pattern on the back, white breast, black 

 head, and white and black bands on the neck. On the land the loon 

 is quite clumsy and makes poor progress in walking. It really never 

 seems to come ashore except for nesting purposes, when it deposits its 

 two large eggs in some slight depression not far from the water's edge. 

 Fortunately, the eggs are of a brownish mottled color and are so 

 nearly in harmony with the background that they are very difficult to 

 detect. 



Another species of loon, the Pacific Loon, has been studied by 

 Coues, who gives the following realistic description of its behavior 

 in the water: 



"Now two or three would ride lightly over the surface, with 

 neck gracefully curved, propelled with idle strokes of their pad- 

 dles to this side and that, one leg, often the other, stretched at 

 ease almost horizontally backward, while their flashing eyes, first 

 directed upward with sidelong glance, then peering into the depths 

 below, sought for some attractive morsel. In an instant, with a 

 peculiar motion, impossible to describe, they would disappear 

 beneath the surface, leaving a little foam and bubbles to mark 

 where they went down, and I could follow their course under the 

 water; see them shoot with marvelous swiftness through the 

 liquid element, as, urged by the powerful strokes of the webbed 



