TAB. XVII. 



Trionyx incrassatus. 



Fig. 



1. Inside view of the carapace, wanting the nuchal plate, half nat. size. 



si — s~. The first to the seventh neural plates, with the connate neural spines and 



arches. 

 pl\ — ph. The eight costal plates of the right side. 

 c\. The place of attachment of the outer end of the first dorsal rib. 

 C2 — 9. The portions of the consecutive dorsal ribs that become connate with the 



costal plates. 



2. Transverse contour of the upper surface of the carapace. 



