156 PRACTICAL HISTOLOGY. 



a male having been rendered insensible by destruc- 

 tion of the brain, or other means, is curarized as 

 before, and laid upon its back, and a longitudinal 

 cut about an inch long: is made with scissors through 



O O 



Fig. 26. 



Flat piece of cork arranged as a frog-stage for viewing the circulation 

 in the web, tongue, mesentery, or lungs. 



Over the small pieces of cork a the tongue cau be fixed ; n can he removed when 

 the slit below it is wauted for the web ; b, cork with a deep groove cut along 

 one side ; to this the iute.sliae is fastened by needle-poiuts, while the mesen- 

 tery rests on a semicircular piece of glass which should fit at the top of the 

 groove. 



the skin of the abdomen about half an inch to the 

 right of the middle line. Before proceeding further, 

 the operator should wait for a minute or two to 

 make sure that there will be no bleeding ; and any 

 blood that may have already exuded should be dried 

 up with blotting-paper. The abdominal cavity is 

 then opened by a corresponding cut through the 

 muscles and peritoneum, taking care, however, to 

 avoid any veins that may be in sight. Having 

 again assured himself of the absence of bleeding, 

 the operator very gently draws out one of the coils 

 of the intestine, with its included mesentery at the 

 aperture. The animal is now to be turned over on 

 its side, and so propped up against the smaller cork 

 that the wound is about on a level with the top. 



