MUltlD-K— SIOMOOONTES— ONYUUOMYS. 105 



of a maguey, in a nest built of lil)res of 'ziiiatc', contuining two little 

 ones." 



Tills tinimnl, comimred witli tlie soinewluit smaller nnd tlic lirigliter- 

 colored aztecus, beurs mucii tlie sanie relations tliat tiic large gray californicus 

 bears to tlie leucopus ("gambeli"), witli which it is associated in Califlirnia. 



Table XXIX. — iJtaiuremmti of three (drji) iiidiriduaU of II. iiELANoriiiiYB (=rHRXiCANUS, DeS.) from 



Soulhem Mexico. 



Mote. — Since writing the preceding, wo liavo examined tbree otlier specimens from Tcbuantopeo, 

 which, if tho same an the types of melanophryf, lessen tbi; cbanccB Ibat tlie latter is different from mexi- 

 canm. Bat tbey differ in many reopecta from tbe specimena Jnut enumerated, being so very much smaller 

 tbnt we cannot satisfy mirselvea of tbeir identity. Tbe tail only exceeds the body in one Hpecinieu, and 

 beru only by little ; in tbe otbera, it is about ns long, relatively, as De Saussuro gives for nicricanus. That 

 these 8|>ecimcuH are not immature is shown by tbe fact that one of Ibem is a nursing female. In color, 

 tbey are almost precisely like the foregoing, but do not show the black ring round tbe eye, nor the dusky 

 spot nt base of tho metatarsus. One of them Is pure white below; another is grayish (it looks as if soiled); 

 while the third has the faintest possible fulvous tinge all along tiie under parts. 



Much more material than that now in our possession will be required to determine the limits of 

 variation of this large, gray, feuoopiM-liko mouse of Mexico, atd Qx the species upon secure basis. 



Taiilk XXX.- 



-itauurrmentt of thre* dried s/jccimens, proiably of .mklakofiirys, Couea (=f MEXIC.VNUS, 

 DeS.), but much smaller. 



Subgenus ONYCHOMYS, Baird. 



HgpudafU' sp. Maximilian, Reise, etc. ii, 1841, 99 (neo uuct.). 

 Hut sp. Aiju. &. Bach., Q. N. A. ii, Xmi, ;t27. 



Onychomyn. Baikii, M. N. A. 1857, 458 (type, Ilnpudccun kucogaftrr, Max.). — CofES, Proc. Acad. Nat. Soi. 

 I'bila. 1874, 182. 



CiiAKS. — Skull strictly as in Heii)>eromi/.s, i)ut molars larger, with sharper 

 salient and reentrant angles. External form departing (rom Hesperomys, and 



ili 



