338 THOMOMYS. 
Color. Upper parts dark umber brown; sides fulvous; under 
parts buffy fulvous; under side of face blackish; feet and apical 
third of tail white. Melanistic phase, which the type represents, is 
slate black all over, except ends of fore and hind feet and the apical 
third of tail and inside of cheek pouches, which are white. 
Measurements. Total length, 217; tail vertebra, 68; hind foot, 3o. 
340. atrovarius (Thomomys), Allen, Bull. Amer. Mus. Nat. Hist., 
1898, p. 148. 
TATAMELES PocKET GOPHER. 
Type locality. Tatameles, State of Sinaloa, Mexico. 
Geogr. Distr. State of Sinaloa, Mexico. Range unknown. 
Genl. Char. Size medium; nasals narrow; similar in color to 
T. orizabe. 
Color. General hue plumbeous, tinged with brown above and 
with gray on the under parts, the tips of the hairs being of that color; 
tail hairs plumbeous and gray. 
Measurements. Total length, 210; tail vertebra, 65; hind foot, 
28; ear, 7. Skull: total length, 40; zygomatic width, 24.5; mastoid 
width, 19.5; interorbital width, 7; length of nasals, 9; width of nasals 
anteriorly, 3.7. 
341. toltecus (Thomomys), Allen, Bull. Amer. Mus. Nat. Hist., 
TO9S; Pe 52, pl. 1, fig. 13. 
JuaREzZ PockEeT GOPHER. 
Type locality. Juarez, northern part of State of Chihuahua, 
Mexico. 
Geogr. Distr. State of Chihuahua, Mexico. Extent of range 
unknown. 
Genl. Char. Larger than T. fulvus. Skull heavy, broad; pre- 
maxilla much longer posteriorly than nasals; interparietal very small; 
upper incisors slightly grooved. 
Color. Upper parts grayish rufescent brown, lined with black 
on median line; under parts pale grayish buff; tail and feet grayish 
buff; edge of cheek pouches white. 
Measurements. Total length, 230; tail vertebra, 60; hind foot, 
27. Skull: total length, 43; basilar length, 40; greatest zygomatic 
breadth, 27; interorbital constriction, 7; length of nasals, 14. 
342. perditus (Thomomys), Merr., Proc. Biol. Soc. Wash., XIv, 1901, 
p. 108. 
Lost PocKET GOPHER. 
Type locality. Lampazos, State of Nuevo Leon, Mexice. 
Geogr. Distr. Range unknown. 
