The skull has each of the zygomatic arches and the anterior end of the nasals broken through. The only part missing is the central two millimeters of the left zygomatic arch. The teeth all are present and entire. The skeleton appears to be complete except for the bones of the feet, which are preserved within the skin. The skin is well made and in good condition. _Range._--Altitudinally, sea level to more than 4000 feet; Sonoran and Transition life-zones of Coast Range and coast of California from San Francisco Bay south to Point Conception, Santa Barbara County, California. See figures 29 and 30 on pages 221 and 314. _Characters for ready recognition._--Differs from _M. f. munda_, _xanthogenys_, and _pulchra_ by having inside of ears darker than back rather than same color as back, and from _xanthogenys_ and _pulchra_ in near (_l_) Antique Brown color of upper parts rather than Buckthorn Brown or near (16 _j_) Buckthorn Brown to near (_h_) Yellow Ocher respectively; from _M. f. latirostra_ by postorbital breadth, of adult males and females, less, rather than more, than width of basioccipital measured from medial margin of one foramen lacerum posterior to its opposite. _Description._--_Size._--Male: Five adults from Palo Alto, Santa Clara County, yield average and extreme measurements as follows: Total length, 447 (412-465); length of tail, 167 (147-175); length of hind foot, 46 (45-47). Corresponding measurements of four adults from San Francisco are: 412 (394-435); 153 (145-160); 43.5 (41-46). Corresponding measurements of five adults and subadults from Berkeley, Alameda County, are: 419 (390-448); 148 (135-160); 44 (42-47). Tail averages 59 per cent as long as head and body in series from Palo Alto and in one from San Francisco. The average of 55 for the Berkeley series probably reflects a lesser average age. Length of hind foot less than basal length. The type specimen measures, 415, 150, 43. It is smaller than the mean. Female: A subadult from Palo Alto measures: Total length, 368; length of tail, 126; length of hind foot, 39. An adult and two subadults from Berkeley measure, respectively, as follows: Total length, 347, 365, 340; length of tail, 134, 123, 125; length of hind foot, 37, 38.4, 36.5. In these four females the tail averages 55 per cent as long as head and body. Length of hind foot less than basal length. The average differences in external measurements of the two sexes, as represented by specimens from Berkeley, Alameda County, are: Total length, 68; length of tail, 21; length of hind foot, 7. Eight adult males weigh 249 (217-335) grams and one adult female 123 grams.