Alimentary Canal. 83 



osmic acid from one to two hours to stain, then place 

 them in one- sixth per cent, chromic acid and complete 

 the hardening in the usual manner. The one- sixth 

 per cent, chromic acid is here used without the addi- 

 tion of methylated spirit. 



Some sections of stomach should be taken from the 

 different parts, pylorus, cardiac end, &c., and these 

 should be stained in logwood ; those which are required 

 to show the peptic cells should be stained in anilin blue. 



Pyloric end of stomach with commencement of duo- 

 denum should be hardened in chromic acid mixture or 

 if the whole stomach has been hardened a portion show- 

 ing the junction of these two parts should be cut with 

 the microtome and double- stained, a few sections also 

 should be stained with logwood. Examine these sec- 

 tions for the gradual change in the epithelium as the 

 one organ passes into the other. 



DUODENUM 



May be hardened in chromic acid mixture and sec- 

 tions stained with logwood. 



Notice Brunner glands cut in different sections, also 

 goblet cells amongst the columnar epithelium and the 

 fine non- striped muscle fibres running up from the 

 muscularis mucosae to the basement membrane. 



ILEUM. 



The whole of the intestine may be hardened in 

 chromic acid mixture or in spirit mixture, page 11, it 

 must not be much handled and should be first slightly 

 washed in very weak solution of chromic acid. Sec- 



G2 



