_Sciurus griseus anthonyi._ Mearns. Anthony Gray Squirrel. Very common in the transition zone. In early spring they start working on pine cones on the mountain tops, gradually coming down to more abundant supplies of food until fall finds them down in the oak belt feeding on acorns. They winter as low as Palmers canyon in some cases. _Entamias Sp._ Abundant in the pine belt and as high as the top of "Baldy." They are good climbers, exceedingly active and bursting with curiosity. _Onychomys torridus ramona._ Rhoads. San Bernardino Grasshopper Mouse. But two specimens of this carnivorous mouse were taken in a period of trapping extending over three months. Both specimens were taken on bait consisting of rolled oats and in the same place, east of Indian Hill in the brush. A good many of my specimens were more or less devoured in the traps in this locality, and I strongly suspect this mouse of the crime. Nowhere else were my mice eaten or were any grasshopper mice taken. _Peromyscus maniculatus gambeli._ Baird. Gambel White-footed Mouse. This species was one of the most common forms taken, being abundant in the brushy valley and foothills. There is a great deal of color variation in the specimens taken. _Peromyscus boylei rowleyi._ (Allen.) Rowley White-footed Mouse. No specimens were trapped in the valley. However these mice were found not uncommon at the mouth of Palmers canyon, just four miles north of Claremont, in the dry brush land. Within the canyon they were common and were taken as high as the top of Ontario peak along fallen logs. At Camp Baldy they are very common especially along watercourses and fallen logs. Indications are that they ignore zonal limits being taken well down in Lower Sonoran zone and in high transition and not necessarily near water. _Peromyscus californicus insignis._ Rhoads. Chemisal Mouse. Not common. None were taken in the valley and few in the canyons. They were not found along waterways but frequently brushy hillsides. This is a large species of mouse and was almost too much for the little "gee whiz" traps to hold. _Peromyscus eremicus fraterculus._ Miller. Dulzura Mouse. Common in the brush land of both valley and foothill, being found in the canyons also. _Reithrodontomys megalotis longicauda._ Baird. Long-tailed Harvest Mouse. Common in valley and foothill. Although partial to grassy areas (I took many in the grassy runways made by meadow mice--Microtus californicus). I found them not uncommon in the dry brush land east of Indian Hill. _Neotoma fuscipes macrotis._ Thomas. Southern Brush Rat. Common from valley to 5,000 feet in the mountains in suitable localities. I took one in the property house at the Greek theatre this June. The large nests are seen very commonly in the canyons and hillsides.