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. 

 ph—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. 



