98 GENERAL BIOLOGY. 



each end of the first. Turn the flaps of skin 

 outward and pin them down. 

 Observe : 



1. On the skin near the shoulder the musculo- 



cutaneous vein. 



2. The body-wall, formed of muscles. 



3. In the median ventral line the anterior ab- 



dominal vein. 



Put a double ligature on this by making a slit 

 on each side of the vein and tying two threads 

 around it near together. Raise the body -ic all 

 with forceps, and with scissors carefully con- 

 tinue the cut on the left side of the vein from 

 pelvis to sternum. Make a transverse cut 

 between the ligatures and extending across the 

 ventral aspect of the body. 

 Note the anterior abdominal vein passing 

 dorsally into the liver. 



With scissors cut in the median line through the 

 sternum and other superficial parts, taking 

 care not to injure the parts beneath. Turn 

 each half outward and pin firmly . 



4. Sketch the organs exposed to view and identify 



them. {Remove the ovaries if they conceal 

 the other organs.) 



(a) The heart. 



(b) The liver : reddish brown and bilobed. 



(c) The lungs. 



