798 REPORT OF STATE GEOLOGIST. 



The incubation period is near three weeks. Both birds share in 

 the labor. They are very watchful of their charges, and many a 

 spirited encounter is had to drive some intruder from the neighbor- 

 hood. Usually,, but one brood is reared each season. When disturbed, 

 they have been known to lay a second and third set of eggs. How- 

 ever, eggs have been found as late as August, indicating, possibly, 

 more than one brood in a season. In July and August, when old and 

 young are found together, along the farm fences, they are most often 

 seen. From the report prepared by the United States Department of 

 Agriculture, we learn that of 320 stomachs examined, 1 contained a 

 game bird; 53, other birds; 89, mice; 12, other mammals; 12, reptiles, 

 or batrachians; 215, insects; 29, spiders; and 29 were empty (Bull. 

 No. 3, Div. 0. and M., Fisher, p. 127). At times it is known to. 

 attack young chickens and beneficial birds. A telegraph line is a 

 favorite place for these Hawks. There, particularly at the time of 

 the spring migrations, every few poles will be found to form a point 

 of observation for them. From this point they wage war upon the 

 mice and other small mammals along the roadway and in adjacent 

 fields. They subsist largely upon grasshoppers, and other insects, 

 especially in late summer and early fall, before the vegetation is cut 

 down by the frost. Upon the Mexican plateau, in winter, I found 

 these birds as much at home as they are with us. They were quite 

 common, and lived chiefly upon insects. The lives of these birds are 

 mostly beneficial. They should receive protection at our hands. 



SUBFAMILY PANDIONINJE. OSPREYS. 

 79. GENUS PANDION SAVIGNY, 



*144. (364). Pandion haliaetus carolinensis (GMEL.). 



American Osprey. 



Claws of the same length, narrower and rounder on under side. 

 Above, plain dusky-brown, tail more grayish, narrowly tipped with 

 white, and crossed by about six or seven narrow bands of dusky; head, 

 neck and lower parts, white; the chest sometimes slightly blotched 

 with brown; sides of head with dusky stripe, top more or less streaked 

 with dusky. 



Length, 20.75-25.00; wing, 17.00-21.00; tail, 7.00-10.00. 



EANGE. America, from northern Brazil to Labrador, Hudson Bay. 

 and Alaska. Breeds throughout its North American range. Winters 

 from South Carolina, and rarely in Southern Indiana, south. 



Nest, bulky, of sticks, reeds, cornstalks, etc., lined with grass, corn 

 blades and other fine material, in top of tree, on cliff, or on ground. 



