774 EEPTILIA. 



The general colour of the upper surface of the shell, in the bright-coloured phase 

 of the male, is rich brown, somewhat marbled with darker in the form of hues, the 

 under surface having a rosy yellow tint. The area around the nostrils is pale bluish, 

 but all the rest of the head, and the under surface of the neck are deep black, passing 

 into a rich crimson on the base of the neck, the whole of the fore-limb being 

 brilliant rosy carmine. The hind limb is dull reddish purple, and the tail and hinder 

 parts are of the same colour, only darker. The eye is a pale greenish yellow. The 

 alveolar or palatal surface of the plates of the jaws is always almost black in both 

 sexes, but darker in the male. 



The skull is distinguished by the contraction of the facial portion, which 

 begins at the posterior margin of the prefrontals ; the region posterior to this being 

 narrow and concave on its upper surface, with the prefrontals in the adult upturned 

 to a greater extent than in any other Batagur. Internal to the sharp finely serrated 

 margin of the maxillaries, there are two parallel strongly serrated ridges on either 

 side of the palate. The anterior ridges are separated from each other in front by a 

 deep mesial groove, continuous with the furrow internal to each, and which is 

 prolonged forwards into the premaxillary depression ; the internal ridges are also 

 separated from each other by a sharp longitudinal ridge; this ridge expands ante- 

 riorly between them, but they are separated from it by the furrow internal to each, 

 sending a narrow prolongation round the anterior extremity of each ridge into 

 the anterior furrow. The hinder border of the palate is slightly reverted, form- 

 ing the posterior wall of the second furrow. The posterior nares have their 

 lateral margins sKghtly anteriorly divergent and not prolonged so far forwards as in 

 B. lineata ; they are thus broader than in that species. The post-palatal portion 

 of the base of the skull, around the nares, is broader and more expanded than in 

 B. lineata, and B. duvaucelU resembles B. haska in this respect, rather than B. 

 lineata. The.pterygoid constriction of the base of the skull is also much broader 

 than B. lineata, and in this character B. duvaucelU also resembles it. It equals 

 half of the space between the pterygoid angles of the post-palatal surface, a pro- 

 portion which also prevails in B. duvaucelU, while in B. lineata it is less than 

 one-third of that interspace. The base of the skull, in this region, does not project so 

 far downwards as in B. lineata. The area between the articular facets for the mandible 

 is only marked by two very shallow concavities on the pterygoids, while in B. lineata 

 there is a deep crescentic concavity, and external to it a deep furrow running 

 downwards and forwards. In B. duvaucelU, this concavity and furrow are merged 

 in one, defined by the ridge that runs inwards forwards and upwards from the inner 

 margin of the facet for the mandible. The concavity on the under surface of the 

 occipital is much larger than in B. lineata,whiGh.i^ the case also with B, duvaucelU, 

 although the superior lateral concavities of the basioccipital are larger and more 

 backwardly projecting in the former species. The parietal region of the skull is 

 also much more flattened than in B. lineata, as it is also in B, duvaucelU, although, 

 in its general form, the skull of the latter is more nearly allied to this species than 

 to the former. The eye, as in other species, is strengthened by a ring of sclerotic 



