CLASS REPTILIA. 



IV.—TmoNYX. GeofF. 

 Feet palmated, claws three, sharp ; the shell covered with 

 a soft skin expanded on the edge into a flexible margin. 

 Living in fresh water in tropical climates. 



I. The margin of the shields cartilaginous and the ster- 

 num narrow. Trionyx, Gray. 



Fierce Trionyoo. Trionyoo Ferox, Merrem. Pen. Phil. Trans. 



Ixi. t. 10. Trionyx Georgicus, Geofi^. 

 Shell rather convex, obscurely keeled ; front and hinder mar- 

 gin wanting ; sternum callosities four, two hinder, large, 

 united into one. Trionyx Spiniferus, Lesueur, Mem. Mus. 

 xi. appears to be the young, as may also be Test. Brong- 

 niartii, Sch. and T. Carinatus, GeofFroy. 



Armless Trionyx. Trionyx Muticus, Lesueur, Mem. Mus. 



XV. t. 



Shell elliptical, confounded with the neck, and armless in the 

 front ; sternal callosities four, two hinder large, united toge- 

 ther. North America. 



Egyptian Trionyx. Trionyx ^gyptiacus, Geoff", Rept. 



Egypt, t. 1. Test. Triunguis, Forsk. 

 Green, white spotted ; shell convex, slightly keeled ; sternum 

 callosities four, the hinder ones triangular, separate. Egypt. 



Indian Trionyx. Trionyx Indicus, Gray, Illust. Ind. 



Zool. t. 



Olive green, with black-edged irregular pale tortuous and 

 forked streaks; sternal callosities four, the hinder ones 

 rounded triangular. India. 



Hurum Trionyx. Trionyx Hurum., Gray, Illust. Ind. 

 Zool. Trionyx Gangeticus, Cuv. Oss. Fos. 



Dull brown ; head green, with two yellow spots on each side 

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