CYCLEMYS OLDHAMI. 15 



CYCLEMYS, Bell. 



Tliorax and sternum solid, entirely bony ; sternum without transverse 

 joint ; a cartilaginous longitudinal suture between sternum and upper shell. 

 Upper shell depressed ; sternum flat ; the suture between the pectoral and 

 abdominal plates curved. Toes distinctly webbed. 



Only one species is known, from British India. 



Cyclemys OLDHAMI. (Plate V. fig. B.) 



Cyclemys oldhami, Gray, MS. 



Form. — Shell moderately elevated, ovate, flat above, with the lateral margins slightly 

 reverted, and with a very distinct vertebral ridge ; there are traces of costal ridges, but they 

 appear to be distinct in young indi\iduals only. Anterior margin entire, posterior distinctly 

 serrated. The vertebral ridge commences from the nuchal plate and is continued to the 

 caudals. The sternum is not quite twice as long as broad, its width between the axillary 

 incisions being equal to that between the inguinal ; it is truncated in front, and has a deep 

 incision behind. 



Plates. — Nuchal plate small, much longer than broad. The first vertebral plate somewhat 

 elongate, bell-shaped ; the three middle vertebral plates as long as broad, the last broader 

 than the caudals ; the caudals separated by a grooved ridge and by a small posterior notch. 

 Gulars subtriangular, longer than broad, the suture between them longer than between the 

 postgulars. Pectorals longer than abdominals ; the transverse suture between pectorals and 

 abdominals is curved, with the convexity backwards. Praeanals about as long as abdominals. 

 The anals vary in form : in the specimen from Mergui they are as broad as long and rather 

 pointed behind, whilst they are broader than long and rounded behind in a specimen from 

 Gamboja. 



Head of moderate size. Front part of the fore limb and heel covered with large, thin, 

 imbricate scales. Fingers slightly, toes broadly webbed. Tail as long as the head. Shell 

 brown above, indistinctly speckled and streaked with black. Sternum with black streaks 

 radiating from the areolar portions of the shields. Head with brown dots above. 



One specimen has been sent by Professor Oldham from Mergui ; another was collected by 

 M. Mouhot in Gamboja ; the shell of both is 8 inches long. 



Figures B, B', B" of Plate V. represent the specimen from Mergui, two-thirds of the 

 natural size. 



