Descriptions, of Xlnc New Ifammals. 105 



seven sp(v-iinens). — Total lenutli. "ioO: tail vertebra', 80: hind 

 toot, ;5(). 



Craii'ml }[('<i--<iireii>ents. — Total length ot" sknll of type, 42: basi- 

 lar length (interior lip of foramen magnnni to jiosterior rim of 

 alveolus of incisor), 85; zvgomatic hreadth, 25; npi)er molar 

 series on alveola^, 0. 



General Characters. — Upper incisors Insected by a median sul- 

 cus ; size smallest of the known species; nose with a vertically 

 elongated naked pad or callosity, above which the hairs are 

 short, stitf, with the tips worn oti"; tail rather long and naked ; 

 claws moderate ; color deep and l)right chestnut above and be- 

 low, much deeper than in Geomys tiiza from Florida and the 

 eastern Gulf region. An inmiature but full-grown specimen 

 (No. 88585) is dusky in color, and one in the molt has the an- 

 terior [)arts chestnut and the posterior dusky. 



f^niiiud Characters. — Geomys nelsonl differs so widely from any 

 of the species having the upper incisors bisected by a single 

 groove that detailed comparison is hardly necessary. Con- 

 trasted with <i. chni-ii from the Kio Gramle region, it ma\^ be 

 distinguished at a glance by its much smaller size, more s(|uarely 

 truncated zygomatic arches, absence of triangular })late at the 

 antero-inferior angle of the zygomatic arch, relatively longer and 

 niore slender nasals, smaller and more smoothly rounded audital 

 bullae, and mastoids which occupy much less space on the 

 occipital ])lane, where they present a subquadrangular surface. 



Mr. Nelson states that the species ''was found only in some 

 fields at the up[)er ranch at the foot of the main north slope 

 of the .Sierra Nevada de Colima, Jalisco, in the upper l)order of 

 the lower pine Ijelt, at about 6,50(.) feet altitude, wliere it was 

 common, and was found in com})any with the large species " 

 [here described as Geoiny--< (lymv^irtis']. Seven specimens were 

 secured. 



Geomys fumosus np. nnv. 



r 



Type Xo. 4?? 3? cf ad. U. S. Xational INIuseuni (Department of Agricalt- 

 ure collection). From Colima City, Mexico, ]March 27, ]Sil2. Collected 

 In' E. W. Nelson. (Original nnnilxT. 2.">.")S.) 



Measurements (iii millimeters, taken in flesh by collector). — 

 Total length, 292; tail vertebra-, 80; hind foot, 41. 



Goin-fit CJiar/irfers. — .Sizemedium. about e(jualling G. hursarius ^ 



