THE MAT AM AT A. 



685 



pen ; and the upper part of the shell was furrowed and marked with 

 large knobs. This concise description gives a fair idea of the principal 

 features of the tortoise which is illustrated in the cut. It is hard to 

 tell which most attracts attention, the large, triangular, depressed head, 



the mouth extending behind the ears, or the doubly furrowed back 

 with its three knobbed ridges. The head ends in a small, movable 

 snout ; the eyes are very small and set far forward ; the sharp jaws 

 are covered with a horny sheath. The neck is thick and bristles with 

 tubercles, and from each side of it hang the ragged membranes which 

 float in the water. The scales of the carapace are raised into promi- 



