The seasons in a tropical rain-forest (New Hebrides).-Part 4. Insectivorous bats (Vespertilionidae and Rhinolophidae).

A review of the literature shows that in temperate latitudes bats usually copulate in autumn. The sperms are stored in the female until spring, when ovulation and fertilization by the stored sperms occur. (Copulation may sometimes occur in spring as well as autumn.) In the remarkably unvarying tropical climate of Hog Harbour, Espiritu Santo, New Hebrides (15° 15'S. in the Pacific), the insectivorous bat Miniopterus australis presents a very sharply defined annual breeding season. Copulation occurs in the part of the year corresponding with the southern spring. Fertilization and development of the embryo proceed without delay. There is no evidence of prolonged storage of sperms in the female, though a few are found in the uterine glands during early pregnancy. Brief reports are made on the reproduction of other species.