1914.] 



SUBGENUS APORODON. 



63 



Specimens examined. — Total number, 18, from the following locali- 

 ties : 



Costa Rica: Volcan de Irazu, 17. 

 Panama: Volcan de Chiriqui, 1.* 



REITHRODONTOMYS AUSTRALIS MODESTUS Thomas. 

 Nicaragua Harvest Mouse. 

 Reithrodontomys modestus, Thomas, Ann. Mag. Nat. Hist., Ser. 7, XX, 1907, p. .163. 

 Type locality. — Jinotega, Nicaragua. 



Distrihution. — Known only from vicinity of type locality. 

 Characters. — Closely similar to australis, but underparts whiter and 

 tail darker. 



Color. — Upperparts mixed black and dull ochraceous-buff, with 

 a fairly well-defined median band of blackish; underparts grayish 

 white, rarely with a faint tinge of light ochraceous-buff and a pectoral 

 spot of the latter color; tail distinctly bicolor, except at the tip, 

 fuscous above, soiled whitish below; ears fuscous; hind feet grayish 

 white; ankles dusky; front feet buffy, with a dusky stripe. 



STcull. — Not seen. Apparently slightly smaller than that of aus- 

 tralis, with smaller audital bullae. 



Measurements. — Type: ^'Head and body, 59; tail, 70; hind foot 

 (s. u.), 16.5; ear, 12.5." Skull: (See table, p. 81). 



Remarlcs. — This form appears to be very closely related to o.us- 

 tralis, but the material at hand is too scanty to show clearly its 

 characters. The color description above is from specimens taken by 

 Mr. Wilham B. Eichardson at San Rafael del Norte and kindly 

 loaned by Dr. J. A. Allen of the American Museum of Natural His- 

 tory. These differ from Thomas's description of the type in having 

 ochraceous instead of ^^drabby" sides and pectoral spot, and tail 

 distinctly whiter beneath. The Richardson specimens are without 

 complete skulls, so a study of the cranial characters has not been 

 possible. Mr. W. H. Osgood, who compared the type specimen with 

 material from the Biological Survey Collection, notes that its skull 

 is slightly smaller than that of australis, the premaxillas shorter, and 

 the audital bullge somewhat smaller. 



Specimens examined: 

 Nicaragua: San Rafael del Norte, 8.^ 



Subgenus APOBODON nobis. 



Type. — Reithrodontomys tenuirostris Merriam. 



Suhgeneric characters. — Upper molars with subsidiary enamel loops 

 in the outer primary reentrant angles, these loops in most species 

 reaching the outer border of the tooth and appearing, when viewed 



1 Collection Mus. Comp. Zool. 



2 Collection Am. Mus. Nat. Hist. 



