208 Notes on the Breeding of a few Western Birds. [March, 
half way down the cafion wall, the bed of which has been cast in 
andesitic lava, and the volume of whose water discharge is re- 
corded in pumice stone. 
These events probably belong, however, to miocene and pliocene 
times, and the topography of this region in those periods—the 
course of the rivers and the configuration of the country must 
for the most part remain unknown. 
Topographic changes of quarternary times are, however, much 
more easily traced. The mass of glacial ice necessary to carry 
the great boulder described above to its present resting place 
would change the whole drainage of the park. The waters of 
the Upper Yellowstone and of the numerous tributaries of the 
lake would be forced across the low continental divide to the 
south and become tributary to Snake river‘and the Pacific, or 
otherwise to some of the western branches of the Missouri. 
-0; 
A COLLECTOR’S NOTES ON THE BREEDING OF A 
FEW WESTERN BIRDS. 
BY E. HOLTERHOFF, JR. 
HE bird fauna of the country lying east. of the Mississippi 
river, has been for years exhaustively studied and written about 
by the resident naturalists scattered over its entire surface ; but 
the great expanse of territory lying west of that river has been 
comparatively little studied, and offers for the naturalist the 
greatest attractions. Especially is this the case in those terri- 
tories, where, until the past few years, the military posts of the 
Government, and a few trading posts, constituted the sole settle- 
ments of the white man. Now, however, the advent of a resolute 
mining population has opened out much new country which will 
steadily continue to develop, and as population pours in, there 
will come some eager and able to investigate and make known its 
treasures of natural history. 
It was with great satisfaction that I found myself in Southern 
California, in the spring of the present year, and at the commence- 
ment of the breeding season of its birds. And although I was 
called away by the first of April, and unable to study any but the 
earliest in breeding, yet a month later I was able to continue my 
studies and collections in the vicinity of Tucson, A. T., and in a 
