574 APPENDIX. 



■well done, this proceeding, which was almost exclusively followed by the 

 ancient anatomists, gives very satisfactory results. It is sxifficient to 

 demonstrate the texture of the glands. 



The Thoracic Duct. — Ligature the jugular and brachial veins near 

 their termination, as also the anterior vena cava about its middle ; lay bare 

 the thoracic duct by cutting the right ribs ; open it near the pillars of the 

 diaphragm, and pour into it two injections of lard, the one before and 

 the other behind the incision. The first injection will fill the duct along 

 •with the venous reservoir, which is intercepted by the ligatures applied 

 to the vessels, as already described ; the second, since it is directed in 

 the opposite direction to the valves, overcomes the resistance ofiered by 

 them, and expands the canal of Pecquet and the chief branches which 

 end in it. Another method is as follows : — One of the branches in the 

 abdominal cavity may be selected, as, for example, one of those united 

 to the colic arteries, near their origin, and the thoracic duct completely 

 injected from its origin to its termination. But this operation requires 

 more practical dexterity than the first, in order to reach the vessel into 

 which the nozzle is to be inserted ; and it is not at all easy to perform 

 it upon fat animals. 



THE NERVOUS SYSTEM. 



The Braijst. — To study the brain, it is first removed from the cranial 

 cavity. This is done by two operations. The first consists of opening 

 the cranium by removing its vault, using a saw, a chisel, and a hammer, 

 after having first removed all the parts covering it. Then open the dura 

 mater with the scissors, and expose the brain, which is to be removed by 

 raising its posterior extremity, and cutting from behind forwards all the 

 nerves issuing from its base, with the pituitary gland, as far forwards as 

 the end of the olfactory lobes. This operation is quickly performed, but 

 it does not permit of the preservation of the pituitary gland, which is 

 strongly fixed in the sella turcica, an inconvenience avoided by employ- 

 ing the following method of opening the cranium at the base. After 

 having separated the head from the trunk, remove the inferior maxilla, 

 the tongue, the hyoid bone, and lay bare the osseous surface, cutting 

 away all the soft parts. The head thus prepared is held by an assistant, 

 the cranial vault being laid upon the table or a block of wood. The 

 operator divides the zygomatic arches and the styloid processes of the 

 occipital ; then divides in succession the condyles of the same bone, the 

 basilar process, the sphenoid, the palatines, the ethmoid ; and returns to 

 the lateral parts, which he cuts through successively from the occipital to 

 the ethmoid. The brain having been thus sufficiently exposed, the dura. 



