THE BIK1>S OF THE PKIJ5I1.0F ISLANDS. 377 



other water birds.' The Cai-t that dirt'ereut species have accomplished similar com- 

 parable results in mature plumage, by roads so strikingly different, argues, I think, 

 an evolutional suggestion of the chronological changes which have taken place. Our 

 knowledge of the relationships of extant to extinct forms is obviously crude and 

 inexact, because of the great lack of precise data and the deficiencies of the known 

 and guessed at geological record; and on tiie other hand one is apt to be misled by 

 not properly discriminating between the purely morphological characters aud those 

 that are partly or entirely aud strikingly adaptive, either on physiological or psycho- 

 logical lines. 



I am fully aware that in thus placing this species at the foot of my ornithological 

 ladder I am doing violence to current opinions; yet considering its life history, its 

 evident generalized low structure, aud lack of advanced specialization, I can not 

 consider it as anything but lower in the avian scale than the other species of water 

 birds to follow. 



The nest of the red-faced cormorant is large, 16 to IS inches in diameter, and is 

 placed in the center of a niche or shelf of the rocks. It is composed almost entirely 

 of sea ferns with a few (piill feathers of the large gulls inserted in the sides, iierhaps 

 for ornament or recognition. The nests are very filthy; insects, es^jecially maggots, 

 swarm beneath them, and evidently they are used for many seasons, with repairs. 

 They breed early. Elliott took two eggs, well incubated, on June 1, 1872, and I 

 secured young, some a week old, on Walrus Island, on June 13, together with eggs 

 more or less advanced in incubation. Some nests contained two, others three, and a 

 few four eggs. Usually the birds leave the nest upon our approaching, but in one 

 case by moving slowly I succeeded in capturing a female by the neck with my hand. 



"From the nest of a cormorant I removed two full grown birds, to all appearances 

 the parents of the brood of chicks, aud I afterwards observed two other adult birds 

 feeding the chicks and taking a parent's care of them." — Lutz. 



The eggs of this species are very small for the size of the birds. The general 

 color is a light, pale blue, over which is deposited, thinly aud thickly, a layer of white, 

 chalky lime, which is roughened by contact with the nesting material. Usually the 

 blue can be seen through this white layer, but often it is thick and can be picked off 

 aud scraped from the bluish surface of the egg. That the white surface layer is soft 

 wheu the egg is deposited is shown especially by No. 1G741, which has several small 

 l)ieces of grassy matter imbedded in the surface, besides numerous imjiressions of 

 otheis. The agga are filthy, as a rule, when in the nest, and wiien advanced in. 

 incubation are apt to be stained yellowish, even when well washed and cleaned. 



The largest and smallest eggs were collected by Mr. Elliott in the summer of 1872, 

 and measure 2.00 by 1.45, 2.26 by 1.57, A set of three taken by myself on June 13, 

 1890, on Walrus Island, measure 2.50 by 1.55, 2.41 by 1.52, 2.36 by 1.54. A single 

 egg taken at the same time is 2.40 by 1.40. I saw several sets of four. 



The following are the weights of seven specimens collected June 13, 1890: Adult 



' Thus in Sula downs are prominently attached to the tips of the flight feathers and their coverts, 

 and in one species at least to the scapulars. Otherwise they are as in I'halacrocorax. The explana- 

 tion is perhaps simple, the higher food-getting habits of iSiiIa having produced and fixed a correspond- 

 ing advancement of feather structure on the parts mentioned, owing to their habitual use. The low 

 grade of the members of this order has permitted a degeneration of the connective portion of the first 

 two feather structures on those parts less concerned in the powers of flight, and which, in Plialacro- 

 corax, has extended to nearly all the feathers. 



