PHALACROCORACIDAE 



75 



grey head, neck, and under sm-faee in the latter. It apparently 

 requires six years to attain the full adult plumage. 



Gannets are oceanic birds, only frequenting the land in stormy 

 weather; they traverse very great distances, and the northern 

 species move southward in winter. The flight is easy and powerful, 

 with alternate flapping and sailing motion, the head being carried 

 in a line with the body and the feet drawn up. The food con- 

 sists of surface -swimming fish, squids, and the like, while the 

 young obtain their nutriment by thrusting their bills into those of 

 the parents, though it is disgorged for them when newly hatched. 

 The prey is chiefly captured by diving, the plunge being made 

 with great velocity from a considerable height and the body 

 being submerged for several seconds; on coming to the surface 

 the bird generally remains quiescent for a short time before 

 again taking to the air, but occasionally swims for a longer period. 

 AA^hen diving the wings are kept open until the last moment, and 

 are then quickly closed. Gannets find the same difficulty in 

 rising from a level spot as do Tropic-birds, and are less prone to 

 perch than naany other sea-birds. The note is a hoarse reiterated 

 sound or, less commonly, a plaintive cry, much noise being often 

 made by the large colonies when breeding. The nest is a mass 

 of sea-weed and grass, placed on a ledge of some high cliff, on 

 the top of a stack, or even on a low tree ; while the eggs — never 

 more than two in number — are occasionally deposited on the 

 bare sandy beach, and are greenish-blue, thickly coated with a 

 white chalky substance, which soon becomes soiled. Incubation 

 lasts about six weeks. The adults, especially in the case of the 

 Boobies, are often absurdly fearless on land, while the female, when 

 on the nest, grunts a,t an intruder, and pecks or bites sharply. They 

 are frequently caught on shipboard by fixing bits of fish on floating 

 pieces of wood, in which the beak is transfixed by the violence of 

 the plunge ; they do not, however, afford palatable food, though in 

 Scotland the Solan Goose is half-roasted and so preserved for eating. 



Fam. III. Phalacrocoracidae. — The genus Fhalacrocorax in- 

 cludes the Cormorants and Shags, birds of similar coloration, which 

 differ chiefly in the brilliancy of their metallic hues and the pro- 

 portion of white to black or brown in the plumage, the follow- 

 ing examples giving a fair idea of the whole. P. carbo, the 

 Common Cormorant, with fourteen rectrices, has the head and 

 neck glossy blue-black, interspersed with white hair-like feathers, 



