CHELONIANS. 473 



open almost vertically, which gives to the animal a strange as- 

 pect. This Turtle exceeds all others in size; the carapace is 

 sometimes fifteen feet in circumference, and nearly seven feet in 

 length. It sometimes weighs more than eighteen hundred 

 pounds. Agassiz states he has seen those that weighed over a 

 ton. The Leathery Turtle feeds upon marine animals, as well 

 as plants. When aged, it is said " to carry on its carapace ** a 

 world of parasites." This gigantic species is found in the Med- 

 iterranean, and in the Atlantic and Pacific oceans. It breeds on 

 the Tortugas or Turtle islands, on the Bahama islands and Keys, 

 and on the coast of Brazil, laying, on an average, about three 

 hundred and fifty eggs, in two sets. A large sized specimen of 

 this species, taken off Sandy Hook in 1816, is now in the Ameri- 

 can Museum, New York city. The Leathery Turtle was known 

 to the ancient Greeks, and of its carapace the first lyre is sup- 

 posed to have been formed ; the seven ridges on the back sug- 

 gesting the adoption of seven strings, which was the ancient 

 number. Hence, it is sometimes called the LUTE TURTLE. 



CHELONIANS. 



Into what divisions may this Order be arranged ? In what respects do 

 they widely diifer from the general form of the class ? What is the shield 

 of the back called? Of what does this consist? What in the TORTOISES 

 represents the sternal or breast ribs of the lizards, &c. ? What is the name 

 of the lower plate of the armor ? What is said of it ? What is the sec- 

 ond distinction between CHELONIANS and other reptiles? How are they 

 compensated for the want of teeth? What is said of the armor of the 

 LAND TORTOISES? What is peculiar in that of the genus Pyxis ? In that 

 of the genus Cinixys ? How is it in the aquatic species ? What is said 

 of the organs of sense in Tortoises? What of their food? Of their pow- 

 ers of abstinence ? Of their growth ? Of their age ? What does Agassiz 

 say of their eggs? Into how many SUB-ORDERS does he divide the order 

 Chelonia? Name the families included in AMYDJS, or DIGITATED TORTOISES. 

 Also those included in CHELONII or PINNATED, (finned, ) T. What groups 

 besides the Land Tortoises does the Sub-order Amydae include ? Into what 

 two divisions are the strictly Marsh Tortoises sometimes arranged ? Are 

 the sp. of this Sub-order numerous ? What is said of the forms of the 

 Land Tortoises? What of their distinguishing characteristics? Of their 

 disposition, habits, &c. ? Name the sp. which are mentioned. Which of 

 these are found in the U. S. ? What is said of it ? What can you say of 

 the others ? 



Which is the 2nd and most numerous FAMILY ? How does the box or 

 armor of these T. differ from that of the Land T. ? Where are the largest 

 part of them found ? How is it with the Cistudo ? What gen. are promi- 

 nent in this family ? Which is the smallest sp. of Emys ? Which is the 

 largest ? What is said of the SALT WATER TERRAPIN ? Which is the most 

 essentially aquatic ? What is said of it ? Which gen. includes the Box 



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