RODEJVTIA GEOMYINAE THOMOMYS BULBIVORUS. 



391 



Bay Company, supposed to have come from the banks of the Columbia. The description of th e 

 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 Eichardson, compared 

 with specimen No. 613, from California, entire in alcohol : 



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 Kichardson 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 douglassii 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. 



