220 GEOMYS. CRATOGEOMYS. 



327. personatus. (GV(W/v.f),True, Proc. U. S. Mus.Wash.,1889, p. 159. 

 Type locality. Padre Island, Texas. 



Gcogr. Distr. Padre Island and mainland to Carrizo on the Rio 

 Grande. 



Gcnl. Char. Size large, colors pale, tail long, basal half haired. 

 Skull: large, heavy; zygomata at right angles to the axis; jugal 

 rounded anteriorly, shorter than basi-occipital; nasals long, narrow; 

 superior profile nearly straight. 



Color. Above pale drab; nose and above eyes dusky; beneath 

 white. Tail, hairs white. 



Measurements. Total length, 339; tail vertebrae, 103; hind 

 foot, 37. 



a.—fallax. (Geoinrs), Merr., Mon. Geom., N. Am. Faun., No. 8, 

 1895, p. 144. 



Type locality. Nueces Bay, Texas. 



Geogr. Distr. South shore of Nueces Bay and lower Nueces 

 River, Texas. 



Genl. Char. Similar to G. personatus, smaller, darker; tail shorter. 

 Skull differs from that of G. personatus in smaller size; shorter 

 ascending arms of premaxilla, more squarely truncate occiput and in 

 much shorter and more swollen audital bullae (Merr., 1. c.) 



Measurements. Total length, 250; tail vertebrse, 80; hind foot, 35. 



59. Cratogeomys. 



I. lUl; p. !=!; M. ^=^ = 20. 



i-i' i-i' 3-3 



Cratogeomys. Merr. Mon. Geom. N. Am. Faun., No. 8, 1895, 

 p. 150. Type Geomys merriami. Thomas. 

 Upper incisor with a single groove, usually open; upper premolar 

 with three enamel plates, posterior absent ; shaft convex forward; 

 upper and lower premolars subequal in length. First and second 

 upper molar with one enamel plate each, posterior absent. Last 

 upper molar with deep sulcus on outer side, none on inner. Skull : 

 a depression extends obliquely across squamosals from root of 

 zygoma to occiput near median line. Breadth of cranium posteriorly 

 less than zygomatic breadth; zygomata broad and heavy. 



328. castanops. {Fseudostoma), Baird, Rep. Stansb. Exped. to Great 



Salt Lake, 1852, p. 313. 



clarkii, Baird, Proc. Acad. Nat. Scien. Phil., 1855, p. 332. 



Type locality. Prairie Road to Bent's Fort, near the present town 

 of Las Animas, Colorado, Arkansas River. 



Geogr. Distr. From Arkansas River in Colorado on Great Plains 

 south through eastern New Mexico and Western Texas to Santa 

 Rosalia, Chihuahua, and Jaral, Coahuila. 



