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Show 410 DR. J. E. GRAY ON THE GENERA OF TURTLES, [Apr. 1, find a second specimen, much less one with the animal; and therefore I have ventured to form a genus for its reception. II. THE LUTHS (Sphargididae) which have the vertebrce and ribs separate both in the young and adult state, as in the generality of vertebrated animals. The bones of the sternum very slightlg developed, and only forming an imperfect marginal ring, being destitute of ang marginal bones. Family I. SPHARGIDIDCE. The outer case of the animal, which has the external appearance of the bony case of a Turtle, is formed of very thick skin studded with close polygonal tubercles, and strengthened with longitudinal ribs supported by larger oval tubercles, which form prominences on the ridges of the back, and especially on the tail of the animal. The head, unlike those of other Turtles, is covered with a soft skin, and is much rounded in front; the nostrils are small, and high up, on a level with the eye; the upper jaw notched on each side; and the lower jaw, which is weak, is furnished with a conical prominence in front, fitting into a hole in the palate of the upper jaw. The nasal hole in the skull is high up from the lower lip, and separated from it a considerable distance by the high large intermaxillary bone, which is large, but not so large, in Caouana or Lepidochelys. The sternum of the very young animal is figured in the ' Annals and Magazine of Natural History,' 1873, t. vi. f. 5. The fore fins are very long, and the finger-bones of the fore and hind fins are rather more regular in length than in other Turtles. 1. SPHARGIS. The adult skull (t. ii. f. 1 & 2) and other parts of tbe osteology of this species are figured by Temminck in the ' Fauna Japonica,' t. ii. & iii. The animal from life, and a front view of its head, are figured in t. i. & v. of the same book. I have figured the skull of the young in the ' Suppl. Cat. Sh. Rep.' p. 119, f. 40 ; and Wagler in the ' N. Syst. Amphib.' t. i. f. 5, 6, & 10-13. Dr. Wagler, in his * Nat. Syst. Amphib.' t. i. f. 1-23, figures the osteology of a newly hatched specimen, showing that the ribs are slender and free for their whole length, and the sternum formed of very slender rudimentary bones, which are divided into a front and a posterior group. In m y paper on the development of the sternum of Tortoises, in the 'Annals and Magazine of Natural History' for March 1873, I described aud figured the sternum of a newly hatched specimen; and I described the vertebral ribs and sternum, as seen on the inside of the skin, of an adult specimen from the Cape, showing that the ribs and sternal bones of the adult are not dilated as in other Che-lonians. The skeleton of the adult in the Museum of Stuttgart, Dr. Krauss informs me, was extracted from a specimen sent in spirits from Suri- |