117 
walls, where it has been since 1892. It may also be of interest to 
know that the surplus peridotite was crushed and used for road 
material in Dewitt with satisfactory results. The rock was hard 
enough to wear well and still sufficiently soft to produce a finely 
packed bedding. Of course there was scarcely enough of the 
material used to pronounce upon its value as a road metal, even 
that which was used being mixed to some extent with the wall 
rock, inclusions, and an occasional bowlder thrown out in the ex- 
cavations. The larger number of fossils which were obtained 
from the inclusions and partly altered adjoining rocks in connec- 
tion with this dike are surprising. In fact not a few of them indi- 
cate geological formations which are now found in place only 
some distance to the southward, and in higher geological horizon. 
THE MAMMALIA OF ONONDAGA COUNTY, N. Y. 
Horace W. BRITCHER. 
JUNE 21, 1902. 
So far as I am aware the mammals of Onondaga County 
have: never been critically studied. I have taken a few mice, 
shrews and bats, but the data from which the present list 1s com- 
piled, are chiefly check marks of species which I have identified 
by the use of Jordan’s “‘ Manual of the Vertebrates.” The at- 
tempt is here made to follow the nomenclature used in the . 
“ Preliminary List of New York Mammals” by Gerrit 5. Miller, 
issued in 1899 as Bulletin 29 of the New York State Museum. 
Onondaga County is situated in the transition zone but the 
difference in elevation, about 1,500 feet, between the northern 
and some of the southern towns, with the presence of deep, 
cool gorges and ravines, and the conditions prevailing at Beaver 
Lake, Cicero Swamp, the Green Lakes and Labrador and Carpen- 
ter Ponds, would seem sufficient warrant for expecting to find 
such characteristic forms of the Canadian zone, as the red-back 
mouse, Canadian white-footed mouse and smoky shrew. 
The county has been under settlement about one hundred 
