DOUBLE-CRESTED CORMORANT. 425 



Feet and claws black. All the silky part of the plumage is greenish- 

 black, at a distance appearing black, but at hand in a strong light green. 

 The imbricated feathers of the back and wings greyish-brown, their 

 fringe-like margins greenish-black ; primary quills brownish-black ; secon- 

 dary like the other feathers of the wing. Tail black, the shafts of all the 

 feathers black. 



Length to end of tail 33 inches, to end of wings 29, to end of claws 

 33 ; extent of wings 51 ; wing from flexure 13 ; tail 6f ; bill along the 

 back ^j%, along the edge of lower mandible Sj^ ; tarsus 2^^ ; outer toe 

 3|, its claw i|. Weight 5 lb. 7 oz. 



The Female is somewhat smaller, but in other respects is similar to 

 the male. 



The Young, after the first moult, have the head and neck mottled 

 with greenish-black and greyish-brown ; the other parts as in the adult, 

 but the tufts on the head wanting. 



The Double-crested and the Florida Cormorants are very nearly allied, 

 their forms, and the structure of their plumage, being precisely similar. 

 There is, however, a very considerable difference in size, as will be seen 

 on comparing their measurements and average weights as given by me. 

 The bills are similar in form, but their colours differ, as do those of the 

 eyelids ; but in the breeding season these birds may readily be distinguish- 

 ed by the temporary tufts or crests behind the eyes, which in P.Jloridanus 

 consist of a mere line of single feathers curved downwards, while in P. dilo- 

 pkus they are of considerable breadth, and composed of about forty recurv- 

 ed feathers. In the absence of the crests, the difference in size affords the 

 principal means of distinguishing them. 



