Vampyressa minuta Miller.--Lactating female, No. 45094, weighed 10.0 grams. At 10:30 A.M. at the outer end of the Armour Trail, Young and Hall had barely paused to listen to animal sounds when they saw this bat alight on a breast-high twig of a bush beneath large trees in the gloom of the forest. Possibly it had been disturbed when the zoologists a few seconds before had pushed aside bushes that partly obstructed the trail. Vampyressa nymphaea Thomas.--Nonpregnant female No. 52455 (403 of Jackson) weighed 10.3 grams and was taken at the Termite Cemetery on May 8. So far as we know, this specimen provides the first record of occurrence in North America of this species which previously had been recorded only from South America. Chiroderma isthmica Miller.--Male No. 45096, April 2; weighed 13.7 grams. Vampyrodes major G.M. Allen.--Male No. 45085, weighed 33 grams. It and the one _Chiroderma isthmica_ on the morning of April 2 constituted the total catch found in the net stretched in the open clearing between two cabins. Artibeus lituratus palmarum J.A. Allen and Chapman.--Nonpregnant female No. 45086 taken on evening of April 7, weighed 68.0 grams. No. 401 of Jackson taken on May 6 weighed 53.5 grams and contained one embryo 12 mm. long; his No. 409 taken on May 10 weighed 53.7 grams and contained one embryo 15 mm. long. Enders (_op. cit._:418) took specimens of _Artibeus jamaicensis jamaicensis_ in Panama and possibly on Barro Colorado Island; he is not specific as to locality. Artibeus cinereus watsoni Thomas.--Male No. 45087 on April 8; weight 13.6 grams. Ingles (Jour. Mamm., 34:267, May, 1953) records the finding of as many as three of these bats on the Island in a "tent" that the bats had made of a frond of the palm, _Geonoma decurrens_. Thyroptera tricolor albigula G.M. Allen.--On May 10 along the Snyder-Molino Trail 50 meters from its beginning Dr. E.R. Dunn found in a curled _Heliaconia_ leaf a group of four bats of this species. A lactating female (No. 405 of Jackson), a young male (No. 406 of Jackson) attached to its mother's teat, and a male (No. 407 of Jackson, now 52457 K.U.) weighed, respectively, 4.8, 2.2, and 4.0 grams. The young one remained attached to the mother when she flew about the laboratory. The fourth specimen, a male, was banded and released. These bats with the aid of suction cups on their wrists and ankles hung head up in the rolled leaf and on places in the laboratory on which they alighted. This species was previously recorded (see Enders, _op. cit._:421) from Barro Colorado Island, on the basis of other specimens also captured by Professor Dunn.