RODENTIA—GEOMYINAE—THOMOMYS BULBIVORUS. 391 
Bay Company, supposed to have come from the banks of the Columbia. The description of th 
mouth and adjacent parts represents very accurately the characters of the group, as may be seen 
by comparing it with the account I give under the head of Geomys, and without a single state- 
ment that is not well founded in fact. The colors of the fur, the contrast of the white cheek 
pouches and chin with the liver brown under the lower jaw, are very accurately indicated, and, 
indeed, as a description of the California gopher, there is little wanting. The feet and tail are 
almost precisely the same. The only discrepancy is in the size of the skin, which is given at 
eleven inches; but a large California gopher would readily stretch to this extent, and all the 
more stable measurements agree very well. In the Smithsonian collections are overstuffed 
skins measuring over nine inches to the root of the tail, which could readily have been extended 
to eleven. 
The following are the principal measurements of the skin described by Richardson, compared 
with specimen No, 613, from California, entire in alcohol: 
D. bulbi- | No. 613. 
vorum. 
Inches. Inches. 
Length of head and body...------------- 11. 00 6.10 
headialone: 2. 22226. 23-.sehsc52 3.00 1. 60 
tailor Sree see pe 2.50 3. 08 
fore foot from heel -...........- 1.00 1.00 
longesticlawecss 25-2 scceeced . 36 seb) 
hind foot from heel..-.---....-- 1. 50 1.50 
longerhclawse S-22eso542s5552 03 ailie 225 
These measurements, it will be seen, agree very closely in all essential features except the 
length, and the disproportion between these is too great not to render it certain that the specimen 
described by Richardson was excessively overstretched. 
The next description of this species was by Eydoux and Gervais, in 1836, from a specimen 
collected at Monterey. Dr. Leconte is in error in referring their animal to the Thomomys 
rufescens of Maximilian, which is widely different. 
The reason that Richardson failed to recognize the close affinity that really exists between his 
Diplostoma bulbivorum and Geomys douglassit lies in the fact that he supposed the cheek pouches 
of the latter to be naturally pendulous from the head, as when inverted in the specimen before 
him. The distortion or contraction of the mouth, too, prevented his noticing the peculiarities 
so evident in the skin of Diplostoma. 
