Note 2433 — BOOK IX. THE NATURAL HISTORY OF FISHES.

He must mean single ones, on each side of the head. Cuvier remarks, that the present passage is from a longer one in Aristotle, Hist. Anim. B. ii. c. 13, which, however, has come down to us in such a corrupt and fragmentary state, that it is totally unintelligible, or, at all events, does not correspond with modern experience. No fish, he says, is known to us that has one or two gills only. The Lophii of the system of Linnæus have three gills on each side, and the greater number of fish four, with a half one attached to the opercule. Some cartilaginous fish, again, have five or six, and the lampreys seven.