76 NEBRASKA ORNITHOLOGISTS' INION 



the head of Warbonnet Canon, where we pitched the camp, that re- 

 mained as our headquarters for the two months of ovir staj'. 



A word of explanation as to the character of the countrj-. The 

 eastern part of Wyoming consists of a high, roughly undulating, grassy 

 plateau, sloping gradually towards the southeast, which, after entering 

 Nebraska, breaks ofE abruptly into the Hat Creek Valley. The face of 

 the plateau along this sudden drop, which ranges from three to five 

 hundred feet, is cut into an endless series of deep, precipitous canons, 

 some of which are short, while others extend back into the plateau 

 for miles, with many twistings and side branches. The longer ones 

 invariably become gradually shallower and finally end on a level wdth 

 the surrounding country, but the shorter ones very often end in an 

 abrupt wall of rock ranging from twenty-five to a hundred feet or more 

 in height. The upper portion of the canon walls is almost invariably 

 composed of "rim rock" rising sheer from ten to even a hundred and 

 fifty feet in height in some places. From the base of this "rim rock" 

 there is a steep slope of earth and rocks to the usually narrow bottom, 

 along which there is to be found in most cases a little streamlet of 

 clear cold water. The slopes are covered with a more or less dense 

 growth of pines (Pinus ponderosa) ranging from a few feet to sixty and 

 seventy feet in height, while the rich soil along the banks of the brooks 

 is thickly overgrown with black birch, quaking aspen, and willow, with 

 an occasional elm and box elder. The innumerable little streams issu- 

 ing from the canons flow out into the valley where they eventually 

 join, to form the stream known as Hat Creek. There is always a thick 

 growth of trees and shrubs along the banks of these valley streams, 

 but it is generally more bushy than in the canons. 



Thus it is easily seen that here is presented a variety of conditions 

 which would be exceedingly hard to duplicate in the same extent of 

 territory. I devoted the major portion of my time to birds, while Mr. 

 Cary was more particularly occupied with the mammals. The follow- 

 ing observations concern the breeding of some of the rarer or less 

 known birds which are to be met with in that vegior : 



Bartramian Sandpiper (Bartramia longicauda). — Although the nest- 

 ing habits of this bird are quite well known, a few observations may 

 not be Avithout interest. The birds were abundant upon the grassy 

 plateau and especially so near the heads of the canons, where its sweet 

 plaintive note could be heard at almost any time. The first nest, which 

 was found by Dr. Wolcott, May 30, contained four fresh eggs of the 

 usual type, and was merely a shallow excavation, probably made by 

 the bird, lined with a fcAv blades of dead prairie grass and was abso- 

 lutely unprotected by any tuft of grass or weeds. The finding of this 

 nest was accidental and careful searching on clear days proved fruit- 

 less; a startled alai-m note woiild be heard somewhere ahead and a 

 moment later a bird would arise, but though we searched the grass 

 fairlv blade by blade no nest could be found. Accordingly, Mr. Cary 



