1918] Kellogg: Microtus calif ornicus Group of Meadow Mice 31 



developed. Coronoid process long, its base narrow, its extremity ris- 

 ing but little above condyle and curved backward. Angular process 

 heavy, curved strongly outward, but with its posterior margin lying 

 in same plane as that of condyle. Peripheral process over base of 

 incisor marked by a conspicuous tuberosity which lies for the most part 

 above masseteric ridge. Base of mandibular foramen situated slightly 

 above cutting surface of last lower molar. Mental foramen on lateral 

 face situated but little below superior surface of diastema. 



Teeth. — Among the meadow mice of the californicus group this 

 race is distinguished by the shortened terminal loop of M-. Anterior 

 loop of Mi crescentic and relatively wide open. No internal lobe 

 present on posterior triangle of M^. The closed triangles are large, 

 and width of molariform series greater than in any other subspecies. 



Lower molars similar to those of californicus but much larger. 

 Transverse loop strongly crescentic, proportionally long, though 

 narrow. 



Remarks. — For some time this race has been included by workers 

 with vallicola. As there is no geographical connection with vallicola, 

 and as characters exhibited by moJiavensis are so distinct, it seems 

 best to regard it as a separate subspecies. It occurs in the bottom 

 lands along the Mohave River well out on the Mohave Desert to the 

 north of tlie San Bernardino Mountains. 



Microtis californicus neglectus, new subspecies 

 Southern California Meadow Mouse 



Arvicola edax, Baird (1857, p. 532), part. San Diego. 

 Arvicola riparius, of some authors, part. 

 Microtus edax, of some authors, part. 

 Microtus californicus, of authors, part. 



Type specimen. — Female adult; no. 19119, Mus. Vert. Zool. ; Es- 

 condido, 640 feet altitude, San Diego County, California ; Februarj^ 7, 

 1913 ; collected by Joseph Dixon. 



Range. — San Diegan faunal district, from Mountain Spring and 

 mouth of Tiajuana River, San Diego County, northwest to Gaviota 

 Pass, Santa Barbara County, and north to Bluff Lake, San Bernar- 

 dino Mountains, San Bernardino County. Vertical range from sea 

 level up at least to 9000 feet ; zonal range Lower Sonoran to Canadian. 

 (See map.) 



Total number of specimens examined, 103, from the following 

 localities in California. San Diego County: Mouth of Tiajuana 

 River, 2 ; Chula Vista, 9 ; San Diego, 1 ; Dulzura, 3 ; Jacumba, 4 ; 

 Mountain Spring, 1 ; Vallecito, 7 ; Cuyamaca Mountains, 4 ; La Puerta 

 Valley, 3 ; Julian, 2 ; Witch Creek, 1 ; Foster, 6 ; Escondido, 4 ; "Warner 

 Pass, 3; San Onofre, 1. Riverside County: Garnet Queen Mine 

 (Santa Rosa Mountains), 1; Hemet Lake (San Jacinto Mountains), 

 2; Round Valley (San Jacinto Mountains), 1; Tahquitz Valley (San 



