WAKREN — NOTES ON WOOD RAT WORK 
233 
others, that makes me think it possible that the latter animal, and U. 
lagomyiarius, and possibly also U. clarki from the Ching Ling, may 
ultimately be found to be generically different from true Ursus, and 
possibly referable to Spelceus. 
NOTES ON WOOD RAT WORK 
By Edward R. Warren 
[Plates 10-11] 
While collecting at Alma, Park County, Colorado, in the autumn 
of 1914, I discovered some unusually interesting work of the “moun- 
tain rat,” or Colorado bushy-tailed wood rat, Neotoma cinerea orolestes. 
This was in an old shafthouse on Buckskin Creek, about a mile from 
the town of Alma. While I have seen much of the work of this and 
other species of Neotoma, in some respects this was very different 
from any I have seen elsewhere. Whether the work of one or two of 
the animals I cannot say, though on one visit to the place I saw two. 
The principal accumulation was about the shaft, which was toward 
the corner of the building, opposite the wide door shown in figure 1. 
This shaft was a two compartment affair, with manway and bucketway, 
the former open at the top, the latter covered with the usual sloping 
doors. About the shaft, but principally about the manhole, and 
even on top of the timbers, were piled many sticks. The pictures 
perhaps show better what a mass of stuff was there. The manway 
measured 30 inches square inside; an outside measurement could not 
be made, biit the base of the pile was 48 inches on one side, and 45 
inches on the other; the material was piled steeply, and much of it was 
green aspen leaves and twigs, just the tips of the branches. As these 
were often piled 12 inches high and 8 inches thick it will easily be seen 
that considerable labor was involved in gathering so much. While 
the accumulation was mainly about the manhole, it also extended 
somewhat along the bucketway, which was the same width, but a 
trifle longer. 
The blacksmith forge in the shafthouse was on the same side of the 
building as the door previously mentioned, by the window which can 
be seen both in the picture of the building and in that of the forge. 
Here were more of the aspen leaves on the forge itself, on a ledge level 
with it, and on shelves and ledges above, five piles altogether. The 
