THE TURTLE. 



Any common species of turtle will answer for the laboratory 

 work. For making out the points mentioned below injection 

 is not necessary. Living specimens may be killed for dis- 

 section with chloroform or ether. If not to be used immedi- 

 ately the plastron should be removed as soon as the animal is 

 killed, so as to permit free entrance of the preservative fluid. 



EXTERNAL. 



The hard shell is composed of a dorsal portion, the 

 carapace, and a flat ventral shield, or plastron. Are the 

 plates covering these arranged in the same way on both? 

 How are carapace and plastron united? Are head, legs, 

 and tail naked? How many toes on the feet? Are claws 

 present? Open the mouth. Are teeth present? Are 

 there lips? Is there a tongue? Do the nostrils connect 

 with the mouth? At the inner angle of the eye see a fold, 

 the nictitating membrane. Pull it out with the forceps. 

 What purpose can it fulfil? Is there an external ear? 



INTERNAL, 



Open the body by sawing the hard parts connecting 

 carapace and plastron on either side, then cut the skin, etc., 

 from the plastron and remove that plate, leaving the ani- 

 mal in the carapace. This exposes the muscles and the 



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