CYTOLOGICAL ANALYSIS OF GONADS DURING SEX UAL-MATURATION OF THE CUTTLEFISH (SEPIA-OFFICINALIS L) FROM THE BAY OF SEINE

A cytological study of germ cells and follicular cells was carried out during- the sexual maturation of cuttlefish (Sepia officinalis) popul ation from the bay of Seine. The results obtained show that, during th e second year of life, an intense multiplication of male germ cells oc curs during August and September. the remaining period of maturation b eing mostly a differenciation phase (spermiogenesis). In female. folli cular cell multiplication (previtellogenesis) occurs in ovary during O ctober and November whereas vitellogenesis begins in December and is p ursued during winter. It appears clearly that, in the aim of an experi mental study of the mitogenic effect of the optic gland gonadotropin o n its target cells, the periods of intense multiplication so establish ed are those in which male germ cells and follicular cells are likely to give an optimal response and should be the most suitable to underta ke experimental studies.