It is proposed to draw attention to an existing species of Selachian obtained by Prof. II. A. Ward along with other natural history specimens in Japan. It was afterwards purchased for the Museum of Comparative Zoology, at Harvard College, and in January, 1884, Mr. S. Garman, of Agassiz Museum, Cambridge, U.S.A., gave a preliminary description of the fish in the Bulletin of the Essex Institute, Vol. XVI., in which he recognised it as belonging to a new family, and confered upon it the generic and specific names at the head of this note. A further contribution, entitled, “A Peculiar Selachian,” appeared in “Science,” a weekly American journal, on Feby. 1st, 1884 (Vol. III., p. 116). In this it is stated that “the body is long and slender, five feet in total length, and less than four inches in greatest diameter; it becomes compressed and thin towards the tail. The head is broad, slightly convex on the crown. The mouth is anterior and very wide. As in other sharks the teeth are arranged in rows across the jaws; they are all alike. Each tooth has three slender, curved, inward-directed cusps, and a broad base, which extends back in a pair of points under the next tooth, thereby securing firmness and preventing reversion. There are six gill openings: the anterior one very wide. Unlike other Selachians, in this, the frill or flap, covering the first opening is free across the isthmus, as in fishes, and hangs down about half-an-inch. The nostrils are ...