J • a. A • 
AMERICAN MUSEUM OF NATURAL HISTORY 
77th Street and Central Park West 
New York February 3, 1909. 
DEPARTMENT OF 
MAMMALOGY AND ORNITHOLOGY 
Tear Mr. Brewster:- _ _ . ... 
Your letter of February 2d with 
enclosure for Bird-Lore is received. 
In regard to names for the two forms of the 
Black Tuck, the proper form would be Anas rubripes 
comrauhis. This is on the basis of the rule of pri¬ 
ority, which affects names and not forms described. 
While communis is the old form, rubrxpes is the ear¬ 
liest tenable name for the group. This is the prac 
tice universally followed so far as I know, and is 
based on the rule of priority as affecting names. 
Sincerely yours, 
Mr. William Brewster, 
145 Brattle Street, 
G arobridge, Mas s• 
