LABORATORY WORK: TURTLE. 



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 

 limb-girdles, and, after the removal of a thin membrane, the 

 viscera. Was either girdle fastened to plastron ? Just be- 

 hind the shoulder-girdle is the heart, and on either side of 

 this the dark liver. In the left lobes of the liver is the 

 stomach. Trace the intestine to the vent. Is there an en- 

 larged terminal portion ? Is the intestine supported by a 

 mesentery ? Do you find pancreas or spleen ? Turn the 

 liver inwards and see the lungs. Are they large ? 



In the heart how many chambers ? From the front see 



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