Osgood — Thirty New Mice of the Genus Pennn.yscus. 77 



Skull. — A bout equal in size to that of P. laylorl ; biuincase narrower and 

 more elongate ; decidedly smaller than in F. rnusciilus : nasals very short ; 

 audital bnlhe very small ; molar teeth small. 



Mcdsttremnita.— Type : Total length, 113; tail vertebrae, 47; hind foot, 

 14; ear from notch (dry), 9.7. Average of G topotypes : 104; 44; 1.'>.4. 

 Skull of type: Greatest length, 18.4 ; basilar length of Hensel,14.6; 

 zygomatic width, 9.6 ; interorbital constriction, .3.2; nasals, (i..'! ; inter- 

 parietal, 5.5 X 1.3 ; iialatine slits, 3.7 ; bony palate, 3 ; upper molar series, 3. 



Remarks. — This diminutive species occurs with F. mmcnlus at Colima, 

 the type locality, and at other localities in western Mexico. It is repre- 

 sented chiefly from the States of Colima and Jalisco, but its range has not 

 been thoroughly worked out and it seems quite possible that it may be 

 found over a considerable area. Apparently it is closely related to 

 F. paid Its * the description of which indicates an animal of about the same 

 size but of different color. 



*Allen, Bull. Am. Mus. Nat. Hist., XIX, pp. 598-599, November 12, 

 1903. 



