Mt. Cacaguatique, Dept. San Miguel, Salvador Nov., 21, 1925 - Dec., 23, 1925 Sonoran Peromyscus Next to the Sub-Tropical Peromyscus the Sonoran Peromyscus were the most common mammal of the Cacaguatique mountain region. Undoubtedly they are as common in the oaks and pines as the sub-tropical form is in its zone, however most of my trapping was confined to the lower zone where more forms were found. I had no difficulty in catching them under logs, among ferns and in old deserted (gopher tunnels) which were caved in many places and partly hidden by fallen oak leaves. Sonoran Peromyscus were found strictly within their own zone, no specimens were taken past the line of oaks and pines. I have no authentic record of scatsorial habits in connection with this form. The same as with the Sub-Tropical Peromyscus the food habits of the Sonoran Peromyscus are omnivorous. Stomachs examined contained chiefly seed pulp, plant pulp, and insect pulp.