360 LAND-BIRDS. 



tooth behind the notch. 123 Highly raptorial birds of medium 

 size. Flight in some respects inferior to that of 



The True Hawks (III, IV). Tarsi not scutellate behind, 

 or feathered to the toes, which are always webbed at the base. 

 Birds of comparatively slender form, with a rapid, protracted 

 flight, occasionally interrupted by straight sailing, even at 

 short intervals. They capture smaller birds with rapidity 

 and energy. 



The Buzzards, including the Eagles (V, VI, VII, VIII). 

 Without the characteristics of the other groups. (In VI, 

 VII, tarsus feathered to the toes.) Heavy and robust birds, 

 with a beautiful and often sublime flight. They frequently 

 sail upwards or forwards without moving the wings, generally 

 doing so in circles. They usually pounce upon their prey 

 from above, and often perch long to watch for it. 



The Fish Hawks (IX). " Plumage lacking aftershafts," 

 and oily. Feet very large. See IX. 



I. CIRCUS. 



A. HUDSONIUS. Marsh Hawk. American Harrier. A 

 common summer resident throughout New England.* 



a. Upper tail-coverts, white. Mature $ , extreme length 

 about eighteen inches. Above, bluish gray, becoming white 

 beneath ; often marked with brown. Wings tipped with 

 black. , extreme length about twenty inches. Upper parts, 

 and streaks beneath, dark brown. Markings above, under 

 parts, and bands on the tail, soft reddish rusty. 



b. The nest, composed of grasses or occasionally sticks, is 

 built, unlike those of all our other Hawks, upon the ground, 

 usually in a meadow, or other wet place. The eggs, of which 

 in Massachusetts four are laid about the tenth of May, aver- 

 age 1.80 X 1.35 of an inch, and are white, often tinged with 

 blue, and often marked with brown. 



c. The Marsh Hawks are among the least ambitious of 



123 The birds of this genus have been land, but at most places seen more 



distributed into several subgenera not numerously during the migrations, in 



here presented. See PI. 1, fig. 27. early spring and late autumn, than in 



* A rather common summer resident the breeding-season. W. B. 

 of practically the whole of New Eng- 



