SACCOMYID^— PEROGNATniDINiE— CRICETODIPUS. 515 



by Mr. E. R. Alston, from examination of the original specimen, kindly 

 made at my request. Mr. Alston writes : — " The type of 'Abromys lordi' is 

 in bad condition, the ears being hopelessly distorted ; but it seems to me 

 to be undoubtedly P. monticola? 



PEROGNATHUS BICOLOR, Gray. 



Honduras Pocket-mouse. 



Perognalhus bicolor, Gray, P. Z. S. 18G8, 202. (Honduras. Description confused with that of a species of 

 Heteiomys — teste Alston, epist.) 



Though not an inhabitant of North America as zoologically understood, 

 this species is introduced to, complete an account of the genus, and to furnish 

 the occasion for correction of an important error into which the describer 

 was led. The original notice is subjoined.* 



Mr. Alston writes me, after examination of the type : — " P. bicolor Gray, 

 (from Honduras,) appears to be a good species, but has been curiously 

 badly described. It is dark brown above, not black, and tho' the fur is 

 sparse and somewhat harsh, it is not in the least bristly ! Gray seems to 

 have had both this specimen and his Heteromys melanoleucus in his hands 

 when he wrote, and to have confused one with the other." 



Genus CRICETODIPUS, Baird. 



= f Crieetodipus, Peai.e, U. S. Expl. Exped. 1848, 52. (Type ?) 



= Cricetodipus, Baird, M. N. A. 1838,418. (Type Perugnathus flavus.)— Gray, P. Z. S. 1868, 202.— Codes, 



Proc. Phila. Acad. 1875, 300. 

 = Otognosis, Coues, Proc. Phila. Acad. 1875, 305. (Provisional name. Type Perognatkus Jlavus.) 



In treating of this form as a subgenus of Perognalhus, Professor Baird 

 clearly showed its external peculiarities, namely, absence of lobation of the 

 antitragus, hairy soles, and diminutive size. To these points are to be added 

 the cranial peculiarities coincident with decidedly greater development of the 

 mastoid than that seen in Perognatkus. The characters having already been 

 given (p. 496), it is needless to repeat them. 



* " PEROGNATHUS BICOLOR, B. M. 



" Perognathus monticola, Gerrard, Cat. Bones B. M. (not Baird). Black; upper lip, lower edge of 

 the cheek-pouch, head, ami under side of body and inner side of limbs white. Fur uniform bristly; 

 bristles elongate, slender, with a slender point, and intermixed with very slender elongated hairs. Tail 

 as long as the body, with rings, square scales, aud short bristly hairs. 



" Hap. Honduras (SalU). 



" There is a Spiny Rat from Honduras * with a longer tail and smooth frontteeth, agreeing in color 

 with tho above." The confusion of ideas intimated by Mr. Alston is here obvious. 



'Characterized on p. 204 of the P. Z. S. for 1868 its Heteromys mdanolcucun, with "Perognathus montico'.or [sic], 

 Gerrard, K. M not S Baird ", quoted as a hynonyui. 



