2i6 A HISTORY OF BIRDS 



Ducks, Birds of Prey, Storks, Cranes, Rails and Wading birds, 

 and probably in many other cases, concerning which, however, 

 we appear to have no records — while in a few cases, as in the 

 Cassowary, Rhea, Tinamous, Painted Snipe, Hemipodes and 

 Phalaropes, the whole work of incubation is performed by the 

 male alone. There are, of course, exceptions to the rule; thus, 

 among the birds of prey the female only incubates in the case 

 of the Harriers, both parents in that of the Buzzards. Among 

 the Sand -grouse the hen broods by day, the cock by night. 

 Where the hen alone sits the males, as in the Ducks, for example, 

 betake themselves off to some distant spot to return on the 

 hatching of the young ; in other cases, as among the birds of 

 prey, the cock remains near at hand to protect his mate and 

 home. 



There are two species of birds which enjoy a unique dis- 

 tinction in the matter of brooding. These are the King and 

 Emperor Penguins. Laying but a single egg, this is most 

 tenderly nursed by both parents alternately, and on the back 

 of the feet. That is to say, the egg, instead of resting on the 

 ground, is supported on the upper surface of the feet, where, 

 pressed close to the body, it is covered by the loose skin of 

 the abdomen and the feathers. Dr. A. E. Wilson, one of 

 the naturalists of the Discovery expedition to the Antarctic 

 during 1901-1904, made a most careful study of the nursing 

 habits of these wonderful birds. A most shrewd and accurate 

 observer, his vivid account of the terrible struggle of these 

 birds to maintain a hold on life will ever remain a model as to 

 how and what to observe in studying the life-histories of animals, 

 and will be the more impressive because of the unusual difficulties 

 and hardships attending these observations. While the bulk 

 of the work would appear to fall on the hen, the cock, as we 

 have hinted, bears his share. But the work of transferring the 

 precious egg is evidently regarded by these fond parents as one 

 of no small importance and delicacy. Consequently a certain 

 amount of ceremonial attends the transfer. The cock, when 

 about to relieve guard, approaches his mate, when both bow 

 one t6 another. He then proceeds to inspect the egg before 

 taking it over, and having satisfied himself that all is in order, 

 assumes charge of the burden. In spite of Dr. Wilson's en- 

 deavours, however, he never succeeded in witnessing the method 



