170 PEROMYSCUS. 
cinnamon coat bordered with white beneath. The majority, how- 
ever, are modestly dressed in the hue for which their familiar family 
name has provided an appellation—mouse color, varied with shades 
of black, russet, and numerous tints of yellows and browns, with 
white harmoniously applied and blended. Usually the under parts 
are white, as are the hands and feet also; but again these latter are 
often plumbeous in different shades. They are the gleaners of our 
fields and woods, often graceful of shape and always agile of foot, the 
““small deer’”’ of our land. 
No careful revision of Peromyscus has as yet been made, and 
until that is done, the status of many of the forms now deemed 
distinct and the arrangement of the species cannot be satisfactorily 
determined. 
42. Peromyscus. Field Mice, Deer Mice. 
I.—; M.— = 16. 
Peromyscus Gloger, Handb. und Hilfsb. Naturg., 1841, p.g5. Type 
Peromyscus arboreus Gloger=Mus_ sylvaticus noveboracensis 
Fischer. 
Calomys Aud., Quad. N. Amer., 11, 1851, p. 303. (nec Waterh., 
Ra Zs0 5 ehos ee pseene) 
Vesperimus Coues, Proc. Acad. Nat. Scien. Phil., 1874, p. 178. 
Batomys True, Proc. U.S. Nat. Mus., 1894, xvi, p. 758. 
Trinodontomys Rhoads, Proc. Acad. Nat. Scien. Phil., 1894, p. 257. 
Haplomylomys Osgood, Proc. Biol. Soc. Wash., XVII, 19¢4, p. 53. 
Size moderate, eyes rather prominent; face rather long, nose 
pointed; ears thin, rather rounded, in some species very large. Feet 
small, digits slender, palms naked; hind feet long, soles with six 
tubercles; tail terete, tapering, slender, hairy, sometimes longer than 
head and body, and occasionally tufted; pelage soft, frequently glossy. 
Skull thin, papery; braincase broad, rather flat, superior outline 
curving both ways from highest point just behind orbits; zygomata 
slender, threadlike, dipping midway to level of the palate, zygomatic 
arch composed mainly of processes of the maxillary and squamosal. 
Orbital foramina just above the level of the alveolus; interorbital 
constriction considerable, but wider than rostrum; nasals and inter- 
maxilla project beyond the incisors; auditory bulle small, thin, and 
obliquely situated; lower jaw straight; coronoid very short; molar 
series short, narrow, the teeth decreasing in size from front to rear; 
upper molars with three roots each, the lower with two, and the un- 
worn teeth have a double series of conical tubercles, which gradually 
are reduced by abrasion, and the pattern varies constantly. 
