Hendrickson 1950 swift water Tadpoles Nov. 21 Buenavista, 4000 ft., Meta, Colombia, S. A. 3 collected (#1589) and a number of others seen, but not collected, in a rushing forest stream (4'-5' wide, about 6" deep). The stream was clear, and fast, running along a bed of boulders and gravel at the bottom of a steep canyon with dense tropical forest growing in all parts of the canyon. Water temp. = 18.6°C. 100% shade (or nearly so) in all parts of creek which I penetrated. The vegetation overhung and enroached over the creek, the creek thus flowed through a sort of low tunnel in the vegetation. Progress along the creek bed was possible only with almost continuous use of a machete. The tadpoles were found in pools where the water was moving less swiftly than in the main, shallow stream course. They may have been in the swift water also, but I could not detect them there. Fast swimmers, they appeared to willingly enter the swift water when disturbed. There was a definite endency to hide beneath stones, and they always attached the mouth firmly to a