458 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxvm. 



APOMYS PETRyEUS, new species. 

 MOUNT APO R0CK-M0U8E. 



7y/^^ Adult feniiile (skin and skull), Cat. No. 125245, U.S.N.M. 

 Collected on Mount Apo at 7,600 feet altitude, southern Mindanao, 

 Philippine Islands, June 30, 1904, by Edg'ar A. Mearns. (Original 

 lunnher, 5600.) 



Chm^acters. — Those of the genus, of which it is the smallest known 

 species. Form and pelage like Peroinijscus. Tail moderately hairy 

 above and below, dark-colored above to the naked tip; caudal annuli 

 about thirteen to the centimeter; hairs of tail about two caudal rings 

 in length on upper surface; soles of feet naked except at the heel. 



C'olor. — The type has the upperparts a beautiful russet or mars 

 brown color; underparts pale fawn color, the colors of the upper and 

 under parts blending on the sides; muzzle, throat, and inner aspect of 

 fore limbs smoke gray; outer surface of fore limbs mouse gra}'; 

 wrists whitish below; feet smoke gray, fading to whitish on toes; 

 claws horn color; tail pale, purplish brown above, flesh color below; 

 whiskers mixed white and brownish black; naked ears drab-gray; iris 

 dark l)rown; hair of upperparts slate-gray at base, of underparts drab- 

 gray. A second specimen, an adult female topotype (Cat. No. 125244, 

 U.S.N.M.), difl'ers from the type in being considerably darker, prin- 

 cipally from a tine admixture of black annuli and tips in the pelage of 

 the upperparts. Front's brown approaches the general eft'ect nearer 

 than any other shade in Ridgway's Nomenclature of Colors. The color 

 of the underparts lacks the cinnamon tinge of the type, being nearer 

 clay color than fawn or cinnamon, and has a tendency to whiteness in 

 the hinder part of the belly. 



Skull (Old teeth. — Braincase swollen in the parietal region; upper 

 profile of skull straight and slightly declining anteriorly, strongly 

 arched posteriorly; audital bull;\? high and rounded; rostrum moderate; 

 nasals expanded apically, tapering gradually to a pointed base oppo- 

 site the fronto-maxillary suture. 



Speciriieiif< examined. — Two adult females (skins with skulls), from 

 a rocky talus at the altitude of 7,600 feet, above the forested portion 

 of Mount Apo, taken June 2S and 80, 1904. 



Cixmial measurement of the type, an adult female, from Mount Apo, Mindanao. 



ISIcasuiviiR'iit. 



Basilar lenRtli (Hensel) 



()cci|iit()-nasal length 



Interparietal breadth 



InterorMtal breadth 



LeiiKtIi (if iiiteriiasal suture 



Aiitero posterior diameter of audital bulla. 

 Length of upper molar series 



No. 125245, 



U.S.N.M., 



type. 



mm. 

 22 

 29.5 

 14 



5.1 

 11.5 



4 



5.8 



