O. G. Dely szerk.: Vertebrata Hungarica 15. (Budapest, 1974)
Topál, Gy.: Field Observation on Oriental Bats. Sex Ratio and reproduction 83-94. o.
I found 20 males and 7 females in a sample collected in Cue phuong(33) between May 8 and 11. One might question the validity of this sample to represent the whole population of 200-300 individuals, but anyway, it means that with a 2.8:1 ratio there is no clear cut segregation of sexes, not even during pregnancy. In Cue phuong(33) the 3 females of this species examined were gravid with 22-24. 5 mm. long embryos on May 8 and 11. On the basis of these one can conclude that in comparison with the population of H. larvatus mentioned, birth takes place 7-10 days later. It is interesting to note that 2 out of 3 embryos were found in the left horn of uterus. Hipposideros fulvus GRAY, 1838 This Indian bat showed rather balanced sex ratio, as in Gwarighat(13) 3 males and 4 females, in Bhaja Caves(8) 2 males and 2 females, and in Elephanta Caves(3) 3 males and 4 females were obtained on March 29,between July 30 and August 6, and on August 30 respectively. In the small cave at Mahableshwar(ll), however, the catch of 12 males and no females was the result of a netting. They were caught late in the evening as they flew into the cave on August 10. A different behaviour of males and females might be the cause of this result. Four females were found in Gwarighat(13) - 3 of them with single embryos - on March 29. Greatest length of fetuses measured 15-16 mm. This observation supports BROSSÉT' s (1962/c) data of birth time in April. I found here a case of twin embryos, both horns of the uterus had a fetus. Hipposideros ater TEMPLETON, 1848 One population of this Indian species (20 specimens) showed a decided 1:1 sex ratio in Konarak(19) on December 26. Hipposideros pomona ANDERSEN, 1918 In small populations I studied in Vietnam at localities around Hanoi(36) pinhvy(30), Co loa(37), Yen so(35)) in some cases the males, in others the females were in majority, e.g. in Dinh vy (30) there was 1 nonpregnant female beside 3 males on April 15. In Tuong linh(34) to some extent a segregation of sexes could be observed, similarly to the case of H. larvatus . In one cave 3 males and 8 females were collected, while in the other the numbers were 11 and 3 between May 20 and 24. One can suppose that the phase of delivery was still on and explains the differences. Two pregnant females taken in Co loa (37) had embryos of 21 mm. long each on April 16. In Cue phuong(33) the only female caught was not gravid on May 8. In Tuong linh(34) out of 3 females obtained 1 was gravid with an embryo of 22 mm. length on May 20. At the same locality, two days later I caught a juvenile which could not fly. Based on data given, it seems as if birth time in this species took place later than in H. cineraceus (see below) and the period itself is more extended. Hipposideros cineraceus BLYTH, 1853 Females occured more frequently than males in localities near Hanoi (36) (Co loa (37X Yen so(35), Xuan dinh(31)) during the period of parturition, that is between April 16 and
