Murray 1448 Balantiopteryx plicata June 2 Cerro Girildo, 600+ ft., 4 mi N San Jose del Cabo, Baja Calif. Dr. Benson and Lewis went to a cave at this location from our camp 2 mi N San Jose del Cabo. There they found many of these bats, the first we have found. Caught about 70 of which I put up 10. (See their notes) June 5 9 mi SW San Jose del Cabo, Baja Calif. 300+ ft. From a wandering Mexican we learned about a cave, which turned out to be far up on the hillside, though in view of the sea. It was washed out of the granite outcropping, 15 feet deep and 12 ft. high. A pothole in the ceiling at the rear contained about 15 bats. These were active and flew out readily. We could only net 4. The rest of them flew around outside rapidly, some trying to re-enter. Their flight seems swallow-like and very skillful. Farther on, past El Tule, Lewis found a cave with more Balantiopteryx June 5 1 mi N Cabo San Lucas Camped a short distance out of town, shot bats in a field. Shot 1 Balantiopteryx and saw many more flying rapidly and irregularly. They seem to be the smallest fastest flying small bat.