38 A BOOK OF BIRDS 



and thousands can be seen, each brooding its single egg. The nest- 

 ling is covered with white down of extraordinary length, and is 

 further remarkable for the great length of time during which it re- 

 mains in the nest. 



Albatrosses, when love-making, behave somewhat strangely. 

 Standing face to face, they start nodding and bowing vigorously, 

 then rub their beaks together, uttering a whistling cry. After 

 this they begin shaking their heads and snapping their bills with 

 marvellous rapidity, occasionally lifting one wing, straightening 

 themselves out, and blowing out their breasts ; then they put the 

 beak under their wings or toss it in the air with a groaning scream, 

 walking round each other meanwhile. And these strange evolutions 

 sometimes last for fifteen minutes at a time ! 



The Manx Shearwater (Plate III. fig. i) may be regarded as 

 a typical Petrel. Though fairly common as a British bird, it is rare 

 in American waters. The legs, we may remark, have been drawn 

 by our artist a trifle too long. 



In the Hebrides this bird breeds in considerable numbers, though 

 in some of the islands, curiously enough, it has been ousted by the 

 Puffin — a much smaller bird, but very pugnacious. On Pabbay, for 

 instance, this Petrel was at one time very common, so much so that 

 the young thereof were so highly esteemed that a barrel of them 

 formed part of the rent paid by each crofter in Mingalay to the Mac- 

 neils of Barra. About a hundred years ago, however, the Puffins 

 began to increase very much, and drove the Shearwaters from the 

 holes which they occupied in the cliffs, and so completely supplanted 

 them that only a few pairs now breed in Pabbay. 



The young of this bird remain in the nest-burrow until long after 

 they are fully fledged, becoming, as a consequence, enormously fat. 



Perhaps the most interesting of all the Petrels is the little Storm- 

 petrel, a kind very closely resembling Leach's Fork-tailed Petrel 

 (Plate III. fig. 2), which is met with quite commonly both in British 

 and American waters. 



The so-called ** Cape Pigeon," which always excites such interest 

 at sea, is a species of Petrel. 



As a rule. Petrels are dark coloured above and white below ; but 

 one species, the beautiful Snow Petrel of the icy regions of the Antarctic, 



