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KEPORT OP STATE GEOLOGIST. 



Family GEOMYIDAE. 



POCKET GOPHERS. 



Form adapted for underground life, with short, strong legs, 

 front feet armed with powerful claws, hind feet also strong, tail 

 short, ears and eyes small, and incisors long and strong. The 

 skin of the cheeks is folded inward, forming pouches which reach 

 from the mouth to the shoulder inside of the outer skin, the open- 

 ing of these pouches being outside of the mouth. 



The family is limited to North America, where it is represented 

 by several genera and a number of species. A single genus is 

 found east of the Mississippi. 



Genus Geomys Rafinesque. 



POCKET GOPHERS. 



Geomys Rafinesque, Am. Month. Mag., Vol. II, No. 1, p. 45, 1817. 

 Dental Formula.— 1, {Ej; C, Pm, M, |e| = 20. 



Generic characters. — Upper incisors, with two grooves, a small 

 one near the inner or midle edge of the front and a deeper one near 

 the middle. Premolar in each jaw with a constriction which makes 

 the enamel pattern the shape of a flattened figure 8. Other molars 

 simple and without any marked constrictions or folds. Skull with 

 a triangular braincase and prominent processes (mastoid processes 

 of the squamosal and bulla) for the attachment of the muscles used 

 in mastication ; region between the eyes constricted ; rostrum long 

 and subcylindrical. 



Form short and stout; eyes and ears small; tail short; nearly 

 naked and extremely sensitive to touch. Claws of fore feet ex- 

 traordinarily long and strong. Large pouches opening beside the 

 mouth into the cheeks. 



The genus contains about 15 species and subspecies in the plains 

 region of the United States and Canada, and with two or three 

 isolated forms in Georgia and neighboring States. But one species 

 is found in the central states east of the IMississippi. 



GEOMYS BURSARIUS (Shaw). 

 EASTERN POCKET GOPHER. 



Mus hursarivs Shaw, Trans. Linn. Soc. of London, Vol. 5, pp. 



227-228 and PI. 5, 1800. 

 Geomys hursarins Merr-iam, N. Am. Faunn, No. 8. p. 120, 1895. 



Fvenriann and Putler, Proc. Ind. Acad. Sci. foi- 1898, p. 126, 



