226 CHELYDIDZ. 
olive-brown, lower surface yellow, with some black spots under the 
neck; a black streak under the ear and another behind the barbel. 
Length of shell 32 centim. 
Brazil. 
6. PLATEMYS. 
Hydraspis, part., Bell, Zool. Journ, iii. p. 511 (1828); Gray, Syn. 
Rept. p. 89 (1831), and Cat. Tort. p. 58 (1844). 
Platemys, Wagler, Syst. Amph. Pp: 135 (1880); Gray, Cat. Sh. Rept. 
i. p. 58 (1855), and Suppl. p. 75 (1870). 
Platemys, part., Dum. § Libr. ii. p. 404 (1835); Strauch, Chelon. 
Stud. p. 45 (1862), 
Acanthochelys, Gray, Ann. § Mag. N. H. (4) xi. p. 805 (1873 
Fig. 61. 
02 PIRATE 
i As, 
» 
ey 
md 
{STEEN ANAT 
al 4 
Shell of Platemys platycephala, 
Neural plates absent ; nuchal shield present, marginal. Plastron 
large, with moderately strong axillary and inguinal buttresses, the 
latter anchylosed to the fifth costal plate. Parietal bones broad, 
expanded above, connected with the strong supraoccipital arch ; 
jaws moderately strong, without alveolar ridges, Chin with a pair 
of dermal appendages, or barbels. Digits webbed. 
South America. 
