PRESIDENT'S ADDRESS. 15 



portion of it. It consists of nine pieces. Both the carapace and 

 plastron are covered by horny plates. The skull of Chelonia does 

 not much differ from the general reptilian type, except in the 

 replacement of the teeth by a horny beak, which invests the 

 margins of the jaws along their whole length. In the carnivorous 

 species the beak is furnished with a sharp cutting edge, the two 

 jaws acting the one against the other, like' the blades of a pair of 

 scissors or shears. On the other hand the working of the jaws of 

 vegetable-feeders is adapted for bruising as well as for cutting. 

 Sir Richard Owen considered the horny beak to be the represen- 

 tative of the two rows of teeth usual with other Reptiles. 



The Order Chelonia is divided into five principal families, 

 it includes the true Turtles characterised by their depressed, 

 flattened carapace, so that when on shore and turned on their 

 backs, they are unable to retain their natural position. The large 

 interspaces between the ribs and sternum are never ossified, but 

 remain cartilaginous, a provision to make the carapace lighter 

 and adapted for the pelagic life of the Turtle. The head is 

 large, and cannot be retracted within the shell. Their habits 

 are essentially marine. The feet are long, compressed, fin-like, 

 and unretractile. They are found hundreds of miles from the 

 shore, to which they periodically resort to deposit their eggs, 

 which they bury in the tropical sands. The most remarkable 

 species is the Leathery Turtle, so called from the soft leather-like 

 substance with which its shell is invested. It is carnivorous, 

 and is found in the Atlantic, Pacific, and Indian Seas. The 

 Loggerhead Turtle, which is also carnivorous, is not found in 

 the Indian Ocean. It is amphibious and met with at great 

 distances from land. The Hawks'-bill Turtle furnishes the 

 valuable tortoiseshell of commerce. Two are recorded from the 

 coast of this county. It derives its name from its elongated, 

 compressed, and curved upper-jaw. The Turtle which is best 

 known, is the Green Turtle, whose flesh affords a luxurious and 

 dainty dish to the gourmand. 



Trionychidae, the so-called Soft Tortoises or Mud-Turtles, are 

 distinguished by the imperfect development of the carapace and 



