410 DR. J. E. GRAY ON THE GENERA. OF TURTLES, [Apr. 1, 



find a second specimen, much less one with the animal ; and there- 

 fore I have ventured to form a genus for its reception. 



II. The Luths (Sphargididse) 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 slightly 

 developed, and only forming an imperfect marginal ring, being 

 destitute of any marginal bones. 



Family I. Sphargidid^e. 



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 longitudiual 

 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 pro- 

 minence 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 inter- 

 maxillary 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 the 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 my paper on the development of the sternum of Tortoises, in 

 the 'Annals and Magazine of Natural History' for March 1873, I 

 described and 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- 



