Description of a new genus of the order Kodentia. 

 By Major John LeConte, U. S. Army, F. L. S. SfC. 



Read December 21, 1829. 



In the pine forests of Georgia, is found a small subterrane- 

 ous animal which is commonly known by the name of Ground 

 Mouse : upon an attentive comparison of it with the known 

 genera of the order Rodentia, I do not hesitate to pro- 

 nounce it different from them all, and constituting a new genus. 

 I propose to call it Psammomysr, from the nature of the soil it 

 inhabits. The teeth somewhat resemble those of the Hypu- 

 dseus of Illiger (Arvicola of others) but the first of the lower 

 jaw has one more triangle, in which it resembles the Fiber 

 (Mus Zibethicus, Linn.) Although externally the animal bears 

 so strong a rememblance to Spalax and Georychus, yet its 

 system of dentition is entirely dissimilar to that of both ; a de- 

 tailed decription of this is omitted, as the plate, which has been 

 drawn and engraved with great care, will give a better idea of 

 it than words can do. 



This animal, like some of its congeners, and like the Sorex 

 and Scalops, forms long galleries under ground: its chief 

 food is roots, and it proves very destructive in fields of the 

 sweet potatoe (Convolvulus batatas.) Being difficult to find, 

 and living almost entirely concealed from view, but little can 

 be known of its habits ; this much however has been learnt, 

 that it never makes its appearance in the day time, and anx- 

 iously avoids every situation where it may be exposed to water. 



PSAMMOMYS. 



Denies primores subexserti, superiores scalpro lato, aequali, 

 Cfestriformi. Molares abrupti, lamellosi. tritorii. contigui. 



