22 TESTUDINATA. — TRIONYCHID^. 



Family III. Trionychid^. 



(Soft Tortoises.) 



These are large Tortoises wliich have no horny 

 shell, but the carapace and plastron are covered 

 with a soft skin. The ribs do not reach to the 

 border of the carapace, nor are they united 

 through the whole of their length, the parts 

 analogous to sternal ribs being replaced by a sim- 

 ple cartilage ; and the sternal pieces are partly 

 dentelated as in the Turtles, and do not cover 

 the whole inferior surface. The feet, like those 

 of the preceding family, are webbed, but not 

 lengthened ; only three toes of each foot are fur- 

 nished with nails. The horny beak is covered on 

 the outside with j&eshy lips, and the muzzle is 

 produced into a short trunk. The tail is short, 

 and the anal orifice of the body is situated near 

 its extremity. 



The Soft Tortoises inhabit great rivers and 

 lakes, where they live upon aquatic animals ; they 

 are eminently carnivorous and voracious, and 

 pursue with agility in tlie water, fishes, and es- 

 pecially young crocodiles. Notwitlistanding the 

 nature of their food, their flesh is esteemed for 

 the table, and hence they are caught with a hook 

 and line : it is necessary, however, as MM. Du- 

 meril and Bibron assert, that the hook should be 

 baited with a living prey, or at least that the 

 motion of apparent life should be communicated 

 to it, if dead, as they are said never to touch a 

 dead or immoveable prey. This does not apply, 

 however, to the eggs of Crocodiles, which the 



