Find information on spaces, staff, and services.
0 UNITED STATES DEPARTMENT OF AGRICULTURE BUREAU OF BIOLOGICAL SURVEY WASHINGTON, D. C. ADDRESS REPLY TO CHIEF, BUREAU OF BIOLOGICAL SURVEY, ,.. =,. :o ( July 12, 1922. AND REFER TO Ti 2 92 BI-IAZ r. Aldo Leopold, Forest Service, Gas and Electric Building, Albuquerque, New Mexico. Dear Mr. Leopold: Your letter of June 30 inquiring concerning the occurrence of the black form of the Abert Squirrel is received. Individuals of this squirrel with blackish underparts appear to occur in various parts of the range of the species and are not uncommon. We have in the collection a number of specimens with blackish underparts from the general region to which you refer, and while there seems to be a tendency to develop this melanistic condition in parts of the range of the species where they are at least more abundant than elsewhere, specimens with dark underparts may be expected to occur elsewhere along with normally-colored individuals. At Loveland, Arkins, and Eastonville, Colorado, melanism is complete in some specimens of Sciuras aberti ferreus, but here as elsewhere normally-colored individuals occur at the same localities. Nelanism as a color variation occurs in many animals, and is perhaps rather particularly comion in squirrels, as it is well known in a number of species. In some squirrels most of the specimens in some localities may be entirely black. Sincerely yours, Chief of Bureau.