372 U. S. P. R. R. EXP. AND SURVEYS ZOOLOGY GENERAL REPORT. 



that the "animal has no tail, no ears, eyes covered hy the skin, and four toes to all the feet." 

 This is, of course, entirely erroneous, and renders it necessary to avoid this name. The genus 

 Geomys is, however, sufficiently characterized in the next paragraph to answer very well for 

 this group, and must be adopted. 1 The genera succeeding, in point of date, though all suffi 

 ciently appropriate to the gophers, are, of course, superseded by Geomys. 



The following brief synopsis may serve to facilitate the determination of species of Geomys. 



A. UPPER INCISOR WITH TWO GROOVES. 



Upper incisor with two grooves, a narrow one near the inner edge, and a deep wide one on or 

 external to the central line of the tooth. Fore feet longer than the hinder, owing to the great 

 development of the fore claws. 



1. Inner groove always distinct; large groove partly involving the central line of 



the incisor. Size large, 7 to 8 inches, fore feet exceeding 1 inches, its longest 



claw three-quarters of an inch bursarius. 



2. Similar to the last, but smaller, 5 to 6 inches ; forefeet less than 1 inches ; its 



longest claw scarcely over half an inch breviceps. 



3. Inner groove obsolete in old age ; large groove situated external to the central line pinetis. 



B. UPPER INCISOR WITH ONE GROOVE. 



Upper incisor with one large groove exactly in the central portion of the tooth. Fore feet 

 not longer, or not as long, as the hinder. 



4. Color nearly uniform yellowish brown darkii. 



5. Color, yellowish brown. Sides of face andhead chestnut castanops. 



6. Color, dark reddish chestnut. Hair very stiff... hispidus. 



7. Very large size. Grayish brown. Hair soft mexicanus. 



GEOMYS BUESARIUS. 



Pouched Gopher. 



Mus bursarius, SHAW, Linnaean Transactions, V, 1800, 237. IB. Gen. Zool. n, 1801, 100 ; pi. cxxxviii. 



MITCHILL, Am. Jour. Sc. IV, 1822, 183. 



Cricetus bursarius, " DESM. Nouv. Diet. XIV, 177." IB. Mamm. II, 1822, 312. 

 GMFF. Cuv. HI, 1827, 138 ; plate. IB. V, 1827, 235. 

 "F. Cuv. Diet, des Sc. Nat. XX, 257." 

 Saccophorus burtarius, KUBL, Beitrage, 1820, 65. 



FISCHER, Synopsis, 1829, 304. 



rseudostama bursarius, SAY, Long's Exped. R. Mte. I, 1823, 406. 

 HARLAN, Fauna Amer. 1825,153. 

 GODMAN, Am. N. H. II, 90. 



ATJD. & BACH. N. Am. Quad. 1, 1849, 332 ; pi. xliv. 

 Gevniys bursarius, RICH. F. Bor. Am. I, 1829, 203. 



Ascomys bursarius, EYDOTJX r GERVAIS, Voyage de la Favorite, V, 1839, 23. 

 1 Mus ludavicianus, ORD, Guthrie's Geog. 2d Am. ed. II, 1815,292. (Not determinable.) 

 Mussaccatus, MITCHILL, N. Y. Medical Repository, XXI, Jan. to June 1821, 249. (From west of Lake Superior. 



Plumbago colored var.) 



Ascomys canadensis, LIGHT. Abb.. Berl. Akad. 1825, 13 ; fig. 

 BEAUTS, Muizen, 1827, 24. 

 WAGNER, Suppl. Schreb. HI, 1843, 383; IB. Abb.. K. Baier. Akad. Miinchen, XXII, 1846, 



327 (figure of skeleton). 

 Geomys canadensis, LECONTE, Pr. Phil. Ac. N. Sc. VI, 1852, 158. 



1 " Feet short, all with five toes and nails ; those of the fore feet very long. Mouth as in the genus Cricetus, and with 

 exterior pouches. Tail round and naked." (Rafimsque, Am. Month. Magazine, II, 1817, 45.) 



