PRELIMIi^ARY DIAGNOSES OF NEW MAMMALS FROM THE 

 MEXICAN BORDER OF THE UNITED STATES/ 



By Edgar A. Mearns, M. D. 



In the collection of mammals made in connection witli the recent 

 resurvey of the boundary line between Mexico and the United States^ 

 are several which appear to be new to science. In view of the probable 

 delay in issuing the complete report on these collections, it seems desira- 

 ble that the new forms should be briefly described in advance. 



SPERMOPHILUS MEXICANUS PARVIDENS, new subspecies. 

 RIO GRANDE SPERMOPHILE. 



Erxleben's " ^ciuriis mexicafius" was based on Fernandez's description 

 of his Tlamototli, and on Seba's " Sciurus rarisshnus, ex Nova Hispanay 

 tceniis albis.^^ No locality was assigned in the inadequate description 

 of Erxlebeu, but Lichtenstein, about 1830, accurately described and 

 figured the species, from a specimen collected by Herr F. Deppe, in 

 July, 1826, in the neighborhood of Toluca, Mexico. We can therefore 

 fix the type locality of Spertno2)hilus mexicanns as Toluca, ^Mexico. 



Comparing six specimens of this species, from Kinney County, Texas, 

 with an adult male — practically a topo-type of 8. mexicanns — froniTlal- 

 pau, Mexico, lent me by Dr. C. Hart Merriam, who kindly furnished its 

 measurements, taken in the flesh by the collector,- tlie Texas specimens 

 prove to be smaller, less yellowish and jialer, with distinctive cranial 

 and dental characters. 



Type. — No. 03073, U.S.N.M. (Coll. International Boundary Commis- 

 sion). Adult male, from Fort Clark, Kinney County, Texas. Collected 

 by Dr. Mearns, March 21, 1893. Original number, 2312. 



Description of type. — Smaller than S. mexicanns ; pattern similar; 

 colors paler, with under parts white, not washed with yellowish brown j 

 tail bushier, its hairs with two instead of three black annuli, and gray- 



Tliis is the second of a proposed series of papers giving preliminary descriptions 

 of the new niainnials collected on the recent survey of the Mexican boundary. 



•Collected by E. W. Nelson, December 2, 1892. Length, 335 mm.; tail vertebriB, 

 148 ; hind foot, 50. 



Proceedings oi'tlio United St.itos Xatiou:il ^Museum, "\'ol. XVIII— Xo. 1075. 

 [Advance slieets of this paiK-r were luibhslied March 25, 1890. J 



443 



