714 DR. J. E. GRAY ON THE DERMATEMYD. [Nov. 1, 
I believe that the genus Dermatemys will be the type of a new 
family, which may be called Dermatemyde, and thus characterized. 
Fam. DERMATEMYD. 
Skull :—the head moderate, rather high, covered with a thin, 
soft, continuous skin ; temples with small polygonal shields; zygo- 
matie arch distinct ; tympanum large, covered with a granular skin. 
Eyes lateral ; iris circular, narrow. Nose produced, conical ; nostrils 
apical, flesh-coloured. Beak strong: upper beak coloured like the 
skin of the head, hard ; lower beak strong, hooked in front. Alveolar 
surface of the upper jaw with a triangular ridge parallel to the outer 
edge of the jaw, and with a short separate transverse ridge in front, 
separated from the front of the beak by a deep pit. Lower jaw with 
three or five strong teeth in front, which fit into the pit in front of 
the upper jaw. The alveolar surface flat, with a deep central groove 
along each side. Chin not bearded. Thorax oblong, the hinder 
edge expanded and slightly reflexed, covered with very thin, mem- 
branaceous shields, which have the areola in the young animals on 
the hinder margin. Sternum flat, united to the margin by a bony 
symphysis, rounded in front and notched behind. Sternal shields 
twelve, very thin, membranaceous. The gular plates small, trian- 
gular, sometimes united into a single plate, with three additional 
intramarginal plates on the suture between the triangular axillary 
and the band-like inguinal plates between the small abdominal and 
marginal plates. The cavity of the shell scarcely contracted at the 
opening. The legs short, fringed on the outer side, granular. Toes 
weak, broadly webbed. Tail short, thick, angular, with ridges of 
spines and a horny tip. 
The head of these animals has much the appearance of Batagur, 
and the shell has a certain resemblance to those of that genus. 
The form of the sternum might be mistaken for that of an Hy- 
draspis ; but it will be found that what looks like the intergular 
plate is, in fact, the small gular plates, which are sometimes separate, 
but usually united together, there being only six pairs of plates, 
without any anterior additional one. 
Synopsis of the Genera. 
1. Dermatemys. Crown flat. Vertebral shields elongate, the first 
the shortest. The gular plates separate or united. 
2. Cutoremys. Crown convex. Dorsal shields wider than long. 
The gular plates united. 
1. DERMATEMYsS. 
Head flat above, rather keeled on the sides. The crown narrow 
and produced behind. Temples with small polygonal shields. 
Thorax convex. Nuchal shield distinct, short. First vertebral 
plate as broad as long; second, third, and fourth longer than broad ; 
the fifth narrow and produced in front, broad behind. Gular plates 
