Volume 14, Issue 6
December 1941, pages 489-577
pp 489-501 December 1941
pp 502-508 December 1941
The development of the egg ofArius jella is very slow and the time taken is two months. The embryo is marked out in the egg on the third day; the eyes make their appearance on the following day. The growth of the embryo is gradual till it is 20 days old; in the following ten days it is rapid and the young hatches out on the 30th or 31st day after the egg is laid. From the time of hatching it takes another month to develop as a young one resembling the adult fish.
pp 509-516 December 1941
The cytology of four species ofStriga, viz., S. densiflora, S. euphrasioides,S. lutea andS. orobanchoides is described. The chromosome numbers have been found to ben = 20 and 2n = 40 in all the four species.
The basic number of chromosomes of the genus is shown to be eight. Based on theoretical considerations it is suggested that in using evidence from secondary associations the most frequent type of association should be taken as indicating the basic number.
pp 517-528 December 1941
pp 529-542 December 1941
The organs of the flower ofLimnanthemum cristatum Griseb., arise in acropetal succession.
The tapetum of the microsporangium is multi-nucleate and shows nuclear fusion.
The diploid number of the species is determined for the first time as 18 and is confirmed from the results of meiotic counts (n = 9). The pollen grains are three-celled at the shedding time.
The embryo-sac shows integumentary tapetum and a chalazal nutritive tissue. Their role in the economy of the nutrition of the ovule is discussed.
The development of microsporangium inEnicostemma littorale Blume., is normal. The tapetum is uni-nucleate. The haploid chromosome number of this species has been recorded for the first time as nineteen.
The development of embryo-sac and embryo are of the normal type.
pp 543-576 December 1941
pp 577-577 December 1941 Erratum