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Show 1870.] DR. J. E. GRAY ON THE DERMATEMYD*. 7 H low, varied with black beneath : the hinder margin entire. Vertebral plates bluntly keeled in front; the first pentangular, twice as long as broad, narrow in front, and gradually narrower and truncated behind ; the second elongate, suddenly narrowed and produced behind and rounded at the end ; the third smaller than the second, pentangular, notched in front, narrow, acute, with a sharp prominent keel behind ; the fourth elongate, oblong, twice as long as broad, six-sided, suddenly contracted and produced in front. Hab. Assam. This species is most like Pangshura tecta ; but the shell is much more ventricose, and the first vertebral plate is much narrower and longer compared with its width, and the second vertebral plate is very differently shaped, as is also the fourth; but this may be an unusual variation. But the lightness, thinness, and ventricose character of the shell marks it as a peculiar species. The fourth, sixth, eighth, and especially the tenth marginal shields have the upper edge produced and more or less extended up between the sutures of the costal shields. 5. O n the Family Dermatemydce, and a Description of a living- Species in the Gardens of the Society. By Dr. J. E. GRAY, F.R.S. &c (Plate XLII.) Mr. Bartlett has sent to me to-day (August 6th) four living freshwater Tortoises to examine and name, recently purchased for the Society's collection, which, I am informed, came from the Laguna de Terminos in Yucatan. They consist of two specimens of Cinosternon with a black head and a yellowish spot over the nose (but as yet I must own I do not know the characters of the species of this genus), an adult specimen oi Emys ornata (the latter animal would not extend its neck, so that I could not see the colour of his head and neck; but it snapped most furiously at every thing that came within a few inches of it, and as rapidly withdrew its head), and a young specimen of what I take to he Dermatemys abnormis of Mr. Cope, which has not before come under m y observation. In the 'Proceedings' of the Society for 1847, p. 55, I described the shell of a large freshwater Tortoise which had been presented to the Society by Lieut. Mawe, R.N., who found it in "South America" in 1833, under the name of Dermatemys mawii. It is peculiar, having the sterno-costal suture covered with four large distinct plates; and I stated that it in this respect agreed with Pla-tysternon, but that it had a very differently formed shell and had much the external appearance of Phrynops geoffroyi, but there was no appearance of any scar on the inner surface of the sternum for the attachment of the pelvis, and that it had no intergular plate. P R O C . Z O O L . Soc--1870, No. XLVIII. |