24 Proceedings of the Biological Society of Washington. 



ochraceous buffy line extends along the outer side of the forearm ; in 

 others, including the type, the entire forelimbs are white. 



Skull. — About like that of P. a. apache. Similar to that of P. a. melan- 

 otic, but larger; mastoids and audital bullae decidedly larger; inter- 

 parietal relatively narrower. 



Measurements. — Type : Total length, 138; tail vertebrae, 65; hind foot, 

 20.5. Average of five adult topoty pes: 138 (134-143) ; 65 (63-69); 20.5 

 (19.5-21). Skull (type) : Greatest length, 23.2; greatest mastoid breadth, 

 12.8; interorbital breadth, 5.2; nasals, 8.3; interparietal, 3.9x3.1; 

 maxillary toothrow, 3.3. 



Remarks. — While Perognathus apache cleomophila resembles P. a. 

 melanotis in color, the skull indicates closer relationship to the pallid 

 form, P. a. apache, of the Painted Desert region. The dark coloration 

 of the upperparts harmonizes well with that of the decomposed lava or 

 cinders of its local habitat and contrasts correspondingly with that of P. 

 a. apache and the lighter sands it inhabits. 



Specimens examined. — Twenty-six, all from the vicinity of the type 

 locality. 



Perognathus apache caryi, subsp. nov. 



COLORADO POCKET MOUSE. 



Type from 8 miles west of Rifle, Galfield County, Colorado. No. 

 148206, & adult, U. S. National Museum (Biological Survey Collection), 

 collected by Merritt Cary, October 4, 1906. Original number 937. 



Geographic distribution. — Valleys of Grand River and other affluents 

 of the Colorado River in western and southwestern Colorado. 



General characters. — Most closely allied to Perognathus apache apache, 

 but larger and darker ; skull more massive and differing in other details. 

 Closely resembling P. a. melanotis in color, but decidedly larger and in 

 cranial characters departing farther than from P. a. apache. 



Color. — Type: Ground color of upperparts near light ochraceous- buff 

 (Ridgway, 1912), pure along broad, conspicuous lateral line from cheeks 

 to hips, the middle of face, top of head and back rather heavily lined 

 with black; underparts, forelimbs and feet white; ears blackish inside; 

 subauricular white spots distinct as in other forms of the group ; tail light 

 brownish or grayish above, white below. A specimen from Coventry is 

 rich ochraceous-buff, this color partially suffusing the underparts. 



Skull. — Similar to that of P. a. apache, but larger and more massive, 

 the braincase higher, more arched ; nasals longer; ascending branches of 

 premaxillae broader ; interparietal slightly larger, more extended antero- 

 posteriorly; mastoid and audital bullae about the same. Contrasted 

 with that of P. a. melanotis the skull appears still larger, with larger 

 mastoid and audital bullae and differs otherwise in the same characters as 

 from P. a. apache. 



Measurements. — Type: Total length, 154; tail vertebrae, 73; hind foot, 

 21. An adult topotype, 145; 73; 19.5. Skull (type): Greatest length, 



