°Sq X | Mackay, Habits of the Double-crested Cormorant. 2C 



movement being in September, some of the flocks then num- 

 bering sixty or more birds. During such migration they are 

 frequently mistaken for Geese or Brant, especially when passing 

 over the land two to three hundred yards high. In very windy 

 and rough weather they have been known to pass over the land 

 very low down, in one instance within ten feet of the ground, but 

 this is very unusual. Mr. Geo. A. Tapley of Revere, Mass., 

 shot one of three (variety not noted) which were standing on the 

 edge of a marsh in that place in the winter, at a time when there 

 was much ice around. They were engaged in eating a sculpin 

 ( Cottus scorpius Linne, subsp. grccnlandicus) ; whether caught 

 by one of them or found on the shore was not known ; the belly 

 and entrails had been eaten at the time he disturbed them. 



The only other resort of these birds in Massachusetts or Rhode 

 Island, of which I am aware, is on the 'Graves,' some rocks 

 situated outside of Boston Harbor, Mass., a place which has also 

 been a noted resting and roosting place for Cormorants for a 

 great many years. Last year in this locality the flight of Cor- 

 morants was apparently large, the birds being more numerous 

 than usual, but for some unknown reason very few remained at 

 this resort. On some days five hundred to one thousand (esti- 

 mated) birds have been known to pass this place while migrating 

 south. They are very gregarious. The Co7nmon Cormorant 

 (P. cardo), like the Common Guillemot or Murre (Uria troile), 

 is uncommon on the Massachusetts and Rhode Island coasts, and 

 is not often taken, as far as I am aware. The Double-crested 

 Cormorant (P. dilophus), as I have here shown, is not at all 

 uncommon. 



The immature birds of P. di!oph?is are of a general brown 

 tint all over, with a greenish shade on the back and upper tail 

 coverts, the lower parts being light brown. The rounded end of 

 the feathers which cover the entire back when the wings are 

 folded are at this period but imperfectly defined, but in the fully 

 adult bird they are dark drab gray, and contrast boldly and har- 

 moniously with the beautiful dark velvety green of the rest of the 

 adult bird's plumage. The adults of /'. dilop/ius seem to vary 

 considerably in size, judging from those I have seen, and the sexes 

 are not distinguishable to the ordinary observer by their general 

 appearance, being apparently alike. The downy young are dark 

 brown all over. 



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