GEOEMYDA GRANDIS. 19 



In a smaller specimen, 4i inches long, from the same locality (Singapore), a wide space 

 between the costal and marginal plates, and another on the middle of the sternum, are not 

 ossified. This, therefore, is a young specimen, and from its size we may conclude that 

 specimens of 8 inches are not full-grown, as has been the belief hitherto, but that the species 

 grows, perhaps, to the size of the specimen on which G. grandis has been founded. The 

 shell is shorter and more circular than in the other specimen, with the margins reverted, 

 and the angles also of the lateral marginal plates are projecting, forming sharp spines, whilst 

 the front and hind marginals are sometimes armed with two or three spines. One or two of 

 the hinder vertebrals may be divided into lateral halves, and each costal plate has a small 

 but vei'y distinct spine at the place Avhich is occupied by a tubercle in the larger example. 

 Gular plates terminating in a small spine pointing obliquely outwards. 



Head. — The upper jaw is armed with two tooth-like points anteriorly, separated by a 

 groove, and is not denticulated on the sides. The upper part of the snout and crown is 

 covered by an undivided hard skin, which is probably leathery in a fresh state ; a temporal 

 shield between eye and tympanum. 



Tail very short. 



Feet. — The forearm and the sole of the hind foot are covered with large, rather thin 

 scales ; no spines on the side of the vent. Claws strong, five anteriorly and four posteriorly ; 

 the fifth hind toe is small and rudimentary. Hind toes with a very distinct web. 



Colour. — Upper part of the shell and the soft parts brown. The specimens from Singa- 

 pore show a yellowish spot on each side of the neck, which is sometimes produced backwards 

 into a streak. The sternum shows a very characteristic coloration, the areola of each plate 

 being yellow, whilst numerous yellow streaks radiate from the areola over the remainder of 

 the plate, which is brown. In very young specimens, where the areola occupies nearly the 

 whole plate, these streaks are short, and in older specimens, where the epidermis is more or 

 less worn ofi", only traces of them remain. 



This species is known to occur in the Malayan Peninsula (Pinang, Singapore) and in 

 Sumatra. Its habits are aquatic, as is proved by the web between the hind toes. 



Geoemtda grandis. (Plate I., and Plate II, figs. A & B.) 



Emys siamensis [Gray, MS.), Giinth. Proc. Zool. Soc. 1860, p. 114. 

 Geoemyda grandis, Gray, Ann. ^ Mag. Nat. Hist. 1861, vi. p. 218. 



Form. — Shell ovate, broader than high, subtruncated anteriorly, somewhat dilated pos- 

 teriorly, with the caudal extremity slightly produced backwards. The front margins are 

 rounded and not serrated, the lateral straight, and the posterior strongly serrated. Its 

 greatest depth is somewhat more than the width of the sternum between the front incisions. 

 The plates are smooth ; a fiat ridfje runs along the vertebral line. The shell is slightly 



d2 



