Note 2773 — BOOK IX. THE NATURAL HISTORY OF FISHES. (continued 2)

It is probable, Cuvier thinks, that this passage relates more especially to the ray genus, but that there is no very positive knowledge as to the mode in which they do couple. It is probable, he suggests, that they may do it in the manner above mentioned, by the attrition of the belly. As to the turtle genus, he says, it is certain that the male mounts the back of the female; and in some species the sternum of the male is concave, the better to adapt itself to the convex callipash of the female.