During a short visit I paid to Oxford in the month of June last I had the opportunity of examining, by the kind permission of Professor Moseley, a number of specimens of Bdellostoma Forsteri, which were some of a large number brought from the Cape by Mr Adam Sedgwick of Trinity College, Cambridge. This examination showed what, from the close affinity of the two forms, was naturally to be expected, namely, that the structure of the reproductive system and the development of the reproductive elements in Bdellostoma were very closely similar to the structure and development of the corresponding parts in Myxine. A short time ago I described before the Society some ovarian eggs of Myxine, obtained at the beginning of the present year, which were approaching maturity. In these eggs there were slight projections at the poles, and on the surface of the projecting parts a number of papillæ. The projections were caused by the growth of a number of threads from the vitelline membrane within the ovarian capsule, and the papillæ were the separate elevations produced by the threads.