Further observations on the structure and function of the nidamental glands of a few elasmobranchs of the Madras coast

Abstract

The structure of the nidamental glands of G. tigrinus, M. nieuhofii, S. blochii and P. micrura is described. Spermatozoa have been observed in the shell-secreting tubules of the nidamental giand of G. tigrinus. 'Tufts' which are characteristic of the lamellæ of other nidamental glands, are absent in the 'lamellæ' of the shell-secreting region of the nidamental gland of M. nieuhofii. No remnant of egg-case is seen in the uterus and it is suggested that owing to the absence of the 'tufts' and the simple structure of the 'lamella' probably no egg-case is formed in this species.