2290 TUBE-NOSED BIRDS, DIVING BIRDS, PENGUINS 



distinctive of that group. This resemblance must, however, be regarded as a purely 

 adaptive one, brought about by the needs of a similar mode of existence, there 

 being but little structural affinity between the members of the two groups. Gener- 

 ally, the tube-nosed birds have a more or less dusky-hued plumage, while they mostly 

 differ from the chattering and screaming gulls by their comparatively-silent habits. 

 Although found in the seas of all parts of the world, the group is represented by the 

 greatest number of species in the Southern Hemisphere, which may consequently 

 be regarded as its headquarters. Very little is known of the group's geological 

 history, although a species of shearwater has been stated to occur in the lower Mio- 

 cene strata of France; the same beds also yielding remains of an extinct genus 

 {Hydrornis) , which has been tentatively assigned to this order. 



THE ALBATROSSES 

 Family DlOMEDElD^ 



The albatrosses are distinguished by their tubular nostrils being placed on the 

 two sides of the beak, and widely separated from one another by the large median 

 portion of its horny sheath. They are further characterized by the extreme length 

 and narrowness of the wing, in which the humerus and ulna are greatly elongated; 

 and also by the large number of quills in the wing, which may vary from thirty-nine 

 to fifty, or more than in any other birds. In the foot the first toe is wanting, while 

 the skull is characterized by the absence of basipterygoid processes on the rostrum 

 of its inferior surface. All the albatrosses (which may be included in the single 

 genus Diomedea) are of large size, and mainly frequent the southern tropical and 

 subtropical seas, although one species ranges on the Pacific coast of America as far 

 north as Alaska. The occurrence of remains of a fossil albatross in the Pliocene 

 deposits of the east coast of England is noteworthy. 



By far the best-known representative of the genus is the wandering albatross (D. 

 exulans] , which is the one represented in our illustration. It belongs to a group char- 

 acterized by the absence of a groove in the horny sheath of the sides of the lower 

 jaw, and also by the length of the wing being equal to three or four times that of 

 the short and rounded tail. The span of wing varies from ten to twelve feet, while 

 the average weight of the bird is only some seventeen pounds. The prevailing color 

 of the plumage is yellowish white, with the quills dusky, and, except in very old 

 birds, the region of the back and the larger wing coverts are irregularly barred with 

 blackish. The beak and feet are whitish. Although the true home of this species 

 is in the south seas, its wanderings occasionally extend to the north of the Equator. 

 The smaller sooty albatross (D. fuliginosa), of the southern oceans generally, and 

 the Pacific, alone represents a second section of the genus, in which the horny sheath 

 of the sides of the lower jaw is marked by a longitudinal groove, while the wing is 

 only about twice the length of the graduated tail. In the adult the plumage of the 

 neck, back, and upper parts is dark ashy gray, becoming lighter on the neck and 



