BIRDS OF MASSACHUSETTS. 267 



the domestic poultry, which it seizes and carries off in the 

 very sight of the farmer. We learn from Nuttall, that one of 

 them, in pursuit of his prey, burst through the glass of the 

 green-house in the Botanic garden at Cambridge, and then 

 through an inner partition of glass, where, his wing feathers 

 being torn by the glass, he was arrested in the attempt to 

 break through a third. Wilson speaks of the slate-colored 

 hawk, as found in the Atlantic states generally ; but its num- 

 bers anywhere must be small. Its nest was found by Audu- 

 bon, in one instance, in a hole in a rock, in others, built with 

 sticks on trees. 



COOPER'S HAWK, Falco Cooperii, was named by Bonaparte, 

 in honor of Mr. William Cooper of New York. It is added to 

 the list of our birds, on the authority of Mr. Samuel Cabot, Jr., 

 who obtained a single specimen in Cambridge. The circum- 

 stance that so little is known of this fine bird, after all the re- 

 searches of eminent ornithologists, shows what a broad field of 

 the science is yet untrodden, and makes it a subject of con- 

 gratulation, that so much zeal and intelligence are now enga- 

 ged in the study. The food of this hawk consists principally 

 of birds ; which, of various sizes, from the ruffed grous to the 

 sparrow, are laid under contribution. In the southern states, 

 they are said, like the preceding species, to be troublesome in 

 consequence of their depredations upon the poultry. 



The ROUGH-LEGGED FALCON, Falco lagopus, and Falco 

 Sancti Johannis were supposed to be two distinct species, till 

 Audubon showed that these, and Falco niger of Wilson, were 

 names of the same bird at different ages ; a mistake easily 

 made, since of eight specimens which Audubon received at one 

 time in Boston, no two were alike in their markings. Their 

 flight was alike, and all their attitudes, as they sat perched on 

 stakes and trees, or flew about pursuing their prey ; but the 

 dark colored birds were much more shy than the light ones, a 

 difference which he ascribed to their greater age. Falco niger, 

 in his opinion, is the old rough-legged falcon. 



These birds are found in the neighborhood of swamps and 



