Observations on the Nidamental Glands of Hydrolagus colliei, Raja rhina and Platyrhinoidis triseriatusi

Abstract

A study of the reproductive system and the nature of the reproduction of the elasmobranchs was started by me in 1940, with the idea of finding out whether or not there is any correlation between the phylogeny and the reproductive structures and habits. Emphasis was laid on such factors as oviparity, ovoviviparity and viviparity and the consequent structural modifications in the nidamental glands; but, owing to many reasons, it was not possible to gather enough data to draw any definite final conclusions. It was, therefore, thought that observations m~de whenever material was available could be published intermittently and final conclusions drawn at a later time.