104 Merriam Three New Jumping Mice (Zapus). 



Zapus pacificus sp. nov. 



Type from Prospect, Rogue River Valley, Oregon. No. 80445, tf yg. ad. 

 U. S. Nat. Mus., Biological Survey Coll. Collected August 29, 1896, by 

 Edward A. Preble. Original No. 1454. 



General characters. Size rather small ; dorsal area strongly suffused with 

 yellowish. 



Color. Dorsal area not strongly defined, but so strongly saturated with 

 yellow that the yellow predominates over the black ; sides buffy yellow, 

 moderately lined with black hairs ; inner side of legs only slightly dark 

 ened; tail sharply bicolor : grayish above, white beneath; fore and hind 

 feet soiled white. 



Cranial, characters. Contrasted with Zapus montanus the skull of Z. 

 pacificus is smaller ; the rostrum and nasals shorter ; audital bullse smaller ; 

 basioccipital broader between bullae ; interpterygoid fossa shorter ; upper 

 molar series more divaricating anteriorly. 



Measurements. Type specimen: total length, 225; tail vertebrae, 141; 

 hind foot, 31. 



Remarks. A slightly younger specimen obtained by Mr. Preble at the 

 type locality has the dorsal area even less distinct, the entire upper parts 

 being ochraceous yellow. A still younger specimen in my private collec 

 tion (No. 3708) from Point Reyes, California, has the upper parts almost 

 uniform deep ochraceous yellow with only the faintest trace of the dorsal 

 area. 



Zapus trinotatus montanus subsp. nov. 



Type from Crater Lake, Oregon. No. 79863, $ ad., TJ. S. Nat. Mus., 

 Biological Survey Coll. Collected August 19, 1896, by Edward A. Preble. 

 Original No. 1388. 



General characters. Size rather large; similar to Z. trinotatus, but some 

 what smaller and duller (sides less ' orange '), with shorter ears and feet, 

 and differing slightly in cranial characters. 



Color. ^ Dorsal area sharply defined, grizzled dusky and yellowish ; sides 

 ochraceous, conspicuously lined with black hairs; inner side of legs to 

 heel dusky; tail sharply bicolor: gray above, white beneath; fore and 

 hind feet soiled white. Belly in young adults washed with yellow. 



Cranial characters. Skull similar to that of Z. trinotatus, but somewhat 

 smaller ; palate narrower ; incisive foramina narrower posteriorly ; angu 

 lar process of mandible less strongly developed. 



Measurements. Type specimen: total length, 231; tail vertebrae, 137; 

 hind foot, 31. Average of eight from type locality : total length, 230 ; 

 tail vertebrae, 135.5; hind foot, 31. 



