297 



Carapace a little depressed, with three keels, the laterals 

 disappearing in the adult; vertebral region flattened in the 

 adult male; posterior margin serrated; nuchal small, broad 

 behind; hind border of first vertebral narrow, not half the 

 length of that shield ; second to fourth vertebrals as long as 

 broad, much narrower than the costals; the postero-lateral 

 sides longest and concave. Plastron smaller than the opening 

 of the shell, truncate anteriorly, angularly notched posteriorly, 

 angulate laterally, feebly concave in the males; width of bridge 



Fig. 109. Bcllia crassicoUls (Gray). Young specimen X ^/s- 



equals the length of the hind lobe; longest suture usually 

 between the abdominals; shortest between the humerals, which 

 is about half that between the gulars; axillary and inguinal 

 shields present. Head large, covered with smooth skin and 

 small shields behind; snout short; mandibular symphysis a 

 little shorter than the diameter of the orbit. Fore limb and outer 

 side of leg with large transverse scales (fig. 107 «); digits 

 entirely webbed, fore limb with five, hind limb with four claws. 

 Carapace dark brown or black; plastron usually variegated 



