Abstract
Some individuals of A. fulica in Malaya have active gonads at all times of the year.
Several criteria indicate, however, that reproductive activity is greatest in July-December
and declines to a minimum in March.
There is some evidence that this cycle is related to rainfall, and that year-by-year
differences in rainfall affect fluctuations in reproductive condition.
A. fulica with their ocular tentacles removed produced significantly more shelled
eggs than normal snails and also had more large oocytes in their gonads. When albumen
glands were full, numbers of shelled eggs were significantly greater than when albumen
glands were reduced. In snails with small albumen glands, removal of tentacles caused
oocytes in the gonad to increase more markedly than shelled eggs.
It is suggested that the general nutritional condition of the snail affects its ability
to form complete shelled eggs, but not its ability to produce oocytes in the gonad. The
latter appears to be under a hormonal control involving the tentacles, rather like that
proposed by Pelluet and Lane (1961).
Subject
Animal Science and Zoology,Ecology, Evolution, Behavior and Systematics
Cited by
16 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献