218 BULLETIN 16 7, UNITED STATES NATIONAL MUSEUM 



The nest was 7% feet up and made of thorny sticks intermixed with bunches 

 of grass. The inside was neatly and compactly made, the lining being of bunch 

 grass neatly placed and a few white breast feathers of the incubatiny bird were 

 in evidence. No food remains were seen anywhere about the nesting site. 



The above nest measured 33 by 26 inches in outside and 11 inches 

 in inside diameter; it was 18 inches in height and was hollowed 

 41/2 inches. The second nest, found 10 days later, was larger, measur- 

 ing 36 inches outside; it was also "located in an Armagosa bush, 

 just waist high to the top and the bottom of the nest 18 inches above 

 ground. The site commanded a view for miles of country around, 

 being on a ridge." He says that the nests are used year after year, 

 as the successive layers indicate. 



The record low seems to be a nest found by G. B. Benners (1887) 

 on Padre Island, "built in the most peculiar situation, being on a 

 Scrub Oak, not more than a foot and a half from the ground. The 

 bush was the only one in sight." And the record high seems to be 

 a nest 15 feet from the ground in a crotch of a large mesquite, from 

 which a set in my collection was taken by E. F. Pope. D. B. Bur- 

 rows (1917) says: 



Most of the nests are built in the tops of thick clumps of thorny bushes com- 

 monly known as the black bush. Two of these nests were placed in the tops 

 of thick clumps of the catcluw, and it is almost as much of a feat to secure 

 the eggs from such nests as it would be to vanquish the angry feline with no 

 weapon of defense in hand. All of the higher nests were placed in small 

 trees, and the mesquite, huisache and hackberry being used. * * « 



The nests of the White-tailed Hawk are composed of coarse sticks at the base 

 with finer sticks in its upper structure, faii'ly well depressed and lined with 

 small tufts of dry bunchgrass pulled from the ground. The latter nests I have 

 found to be similarly constructed, but the lining in them will consist in part or 

 wholly of green leaves from the mesquite and from the huisache trees. Like 

 the other buteos this hawk will use the same nest year after year, adding to it 

 each year until it becomes quite bulky. 



Eggs. — The white-tailed hawk lays usually two eggs, sometimes 

 three and occasionally onh^^ one. Of 30 sets collected by Mr. Bur- 

 rows (1917), three contained one egg each, 26 contained two, and 

 only one set contained three. The proportion of sets of three in col- 

 lections is greater than this. The eggs are ovate, oval, or elliptical- 

 oval in shape, and the shell is smooth or finely granulated. The 

 ground color is dull white or very pale bluish wliite. About one- 

 third of the eggs are unmarked. Others are faintly and sparingly 

 marked with small spots of pale, dull browns, or buffs, "clay color", 

 "cinnamon-buff", or "pinkish buff", rarely with "chestnut-brown" and 

 occasionally with underlying lavender spots. The measurements of 

 50 eggs average 58.9 by 46.5 millimeters ; the eggs showing the four 

 extremes measure 65 by 50 and 52.7 by 42.2 millimeters. 



Plumages. — The downy young of the white-tailed hawk is an odd- 

 looking chick quite different from other young hawks. It is entirely 



