468 MONOGRAPHS OF NORTH AMERICAN RODENTIA. 
Meriones canadensis, LEss., Man. i, 1827, 258.—SCHINZ, Syn. Mamm. ii, 1845, 91. 
Dipus americanus, Barton, Amer. Philos. Trans. iv, No. xii, 1799, 115 (plate, not numbered, opp. p. 124).— 
BARTON, op. cit. vi, 1804, 143 (habits).—Orp, Guthrie’s Geog. 2d Am, ed. 1815, 292. 
Mériones americanus, Fr. Cuvrmr, Dents des Mamm, 1825, 187. No. and pl.75, figs. a, b (teeth. Name not 
formally presented, but inferable from the context). 
Jaculus americanus, WAGLER, Natiirl. Syst. Amphib. 183), 23. 
Meriones americanus, DEKay, N. Y. Zo6l. i, 1842, 70, pl. 24, f. 2. 
Dipus labradorius, TURTON, Syst. Nat. i, 1806, 99 (Labrador Rat of Pennant).—OrpD, Guthrie’s Geog. 2d 
Am. ed. 1815, 292. 
Mus labradorius, J. SABINE, App. Frankl. Journ. 1823, 661. 
Gerbillus labradorius, HARLAN, Fn. Amer. 1825, 157 (after Sabine).—Gopman, Am. Nat. Hist. ii, lst ed. 
1826, p. —; 2d ed. 1831, 97; 3d ed. 1861, 97.—Grirritn, Anim. Kingd. v, 1827, 240, No. 625. 
Dipus labradoricus, FiscuEr, Syn, Mamm., 1829, 338. r 
Meriones labradorius, R1cHarDson, F. B.-A. i, 1829, 144, pl. 7.—WaGner, Suppl. Schreb. iv, pl. 226 B 
(after Richardson).—Dawson, Edinb. N. Philos. Journ. new ser. iii, 1856, 2. 
Meriones labradorus, SCHINZ, Syn. Mamm. ii, 1845, 92. 
Jaculus labradorius, WAGNER, Suppl. Schreb. iii, 1843, 294.—GIEBEL, Siing. 1855, 599; Zeitschr. gesammt. 
Naturw. xxv, 1865, 272 (osteology).—KrnnicotTr, U. S. Patent Office Agric. Rep. for 1856, 
1857, 95, pl. 11 (habits)—MAxXIMILIAN, Arch. Naturg. 1861, p. — ; Verz. Reise N.-Am. 1862, 146. 
Gerbillus sylvaticus, ‘“‘ MircHiLi” (deser. nulla). 
Meriones nemoralis, Is. GEOrFROY, “ Dict. Class. vii,323; pl. fase. 10, n. 2”. 
Gerbillus daviesti, RAFINESQUE, ‘‘ Préc. Découy. Sémiol. 14”. 
? Gerbillus soricinus, RAPINESQUE, ‘ Préc. Découy. Sémiol. 14”.—DESMAREST, Mamm. ii, 1822, 322 (com- 
piled from Rafinesque).—Lesson, Man. i, 1827, 257 (compiled from Rafinesque). 
 Dipus soricinus, FIscHER, Syn. Mamm. 1829, 339 (compiled from Rafinesque). 
? Gerbillus leonurus, RAFINESQUE, Am. Month. Mag. 1818, 446.—DrsMarest, Mamm. ii, 1822, 322 (compiled 
from Rafinesque).—Lrsson, Man. i, 1827, 257 (compiled from Rafinesque). 
? Dipus leonurus, FiscuEr, Syn. 1829, 339 (compiled from Rafinesque). > 
¥ Gerbillus megalops, RAFINESQUE, Am. Month. Mag. 1818, 446.—DrEsMarest, Mamm. ii, 1822, 322 (compiled 
from Rafinesque).—Lrsson, Man. i, 1827, 257 (compiled from Rafinesque). 
? Dipus megalops, FISCHER, Syn. 1829, 340 (compiled from Rafinesque). 
? Gerbillus macrourus, RAFINESQUE. 
? Gerbillus brachyurus, RAFINESQUE. 
Meriones microcephalus, HARLAN, Proc. Zo]. Soe. Loud. vii, 1839, 1—Scninz, Syn. Mamm. ii, 1845, 92 
(compiled from Harlan). 
Meriones acadicus, DAWSON, Edinb. N. Philos. Journ. new ser. iii, 1856, 2, pl. 1. 
Canada Rat, PENNANT, Quad. ii, 172. 
Labrabor Rat, PENNANT, Hist. Quad. 1781, 435, No. 295; Aret. Zool. i, 1784, 132, No. 63. 
Jumping Mouse of Canada, Davies, |. ¢. 
Labrador or Jumping Mouse, GODMAN, 1. ec. 
Canadian Jerboa, SHAW, 1. ¢. 
Labradore Jerboa, TURTON, 1. ¢. 
Canadian and Labrador Gerbil, GrirrirH, 1. ¢. 
Deer Mouse, DEKayY, 1. ¢. 
Gerbille du Canada, DESMAREST, 1. c. 
Mérione du Canada, Lesson, 1. ¢, 
Gerbille soricine, de la baie @ Hudson, queue de lion, et aux yeux noirs, Luss., |. ¢. 
Canadische, Labradorische, Kleinkipfige Hiipfmaus, SCHINZ, |. ¢. 
DESCRIPTION. 
A. Cranial characters—In comparison with the Murine forms with which 
it has been associated, this animal presents many strong peculiarities of the 
skull and teeth. Among these may be enumerated the presence of an addi- 
tional tooth in the upper molar series, causing an inequality in the formulse 
of the two jaws; the size and shape of the anteorbital foramen, with its 
