Weston 1946 Journal 38 July 15 3/4 mi E Keys View, 5000', Riverside Co., California. fleeting about this same place. We couldn't decide whether they were attracted to the light colored hood, the highlight on it making them think it was water or whether the shot bat in the sac was giving sounds that attracted them. Picking the sac up we each heard a very peculiar sound coming from the bat. To me it sounded almost exactly like the humming of telephone or light wires out in the country. You can put your ear against a telephone or light pole and hear this sound. This sound, a supersonic sound was coming from the bat in the sac and possibly was attracting the other bats. We put a pan of water and the bat back on the car hood but no other bats were attracted. The sounds also became fainter from the bat. These sounds, apparently almost beyond the reach of the human ear, could be heard only when the bat was held up close to the ear. The source of the sound, which had no tonal quality, was questionable. It couldn't have come from the vibrating of the bats wings as its wings were pretty badly shot up and the membranes were torn. Possibly it was a vocal sound. Possibly not.