JESimpson, 1938. 70 270ft, Rancho de Costa Rica, Rio Sonora, Sonora. May 4, 1938, continued. off about one-half hour after sunset while it was still quite light--much lighter and earlier than at times seen and caught at water-tank. The mastiff bat flew at about "dove-speed" and seemed an ex- cellent and graceful flyer. It could be heard squeeking sharply as it flew away. This squeeking was noted as they flew over the water-tank with a squeak about every second, but with increased or less tempo as they dove down to water-surface--usually 3 or 4 dips down before touching water--and a loud squeek usually when stopped by the wire. These large bats, as well as the brown bats and Mexican- free-tails, are good swimmers moving rapidly over the surface in a crawling movement, similar to that of ground crawling. The smaller bats could often take off from the surface of the water if not hard hit by wire, and also they could climb the brick-wall of the water-tank; the mastiff bats could do neither. All three of us worked on the bats; then broke camp and drove to: Puerto Kino, Sonora. [=Bahia Kino] Many quackles at Rancho de Costa Rica (at least two of which had yellow eyes as seen from few feet) with hundreds of doves (mourning doves, white-winged doves, Mexican ground-doves, and Iuca doves) which come here to drink; we saw quail as we drove out from the ranch,