XII. On the mode of breeding of the oviviviparous shark, and on the aeration of the fœtal blood in different classes of animals

Abstract

That some of the shark tribe do not lay their eggs, but hatch them within the body, and that others lay them in the same manner as the skate, has long been known; but nothing seems to have been accurately made out upon either of these subjects, I am therefore induced to lay before the Society the following observations. In my examination of the squalus maximus, an account of which is published, I found that it closely resembled in its in­ternal structure, the squalus acanthius of Linnaeus, a fish common on the Sussex coast, which made me pay particular attention to the anatomy of all the parts of this species of dogfish.