200 THE AMERICAN MONTHLY [July, 



The papillce of taste. — Examine the foliated or the 

 calciform papillsB on the posterior lateral and the post- 

 erior borders of the rabbit's tongue. Select a small 

 piece well freed from the surrounding tissues; put it in 

 1 per cent osmic acid. In 12 hours wash in water for 

 24 hours ; harden by gum and alcohol. Section, stain in 

 alum carmine, mount in glycerine. 



Impregnation by gold gives fine preparations. Lemon 

 juice, ten minutes ; 1 per cent chloride of gold, forty 

 minutes. Reduce in acidulated water as directed for 

 nerve endings in muscles. 



Mucous membrane of the pharynx. — Dissect out one 

 portion from the upper, another from the lower part of 

 the pharynx. Spread them in a saucer of 95° alcohol, 

 harden in gum and alcohol. Section, stain in picro-car- 

 mine, mount in glycerine. 



The frog is most useful for the study of ciliated ep- 

 ethelium of the pharynx. Scrape the pharyngeal wall 

 with a scalpel and place the result in a drop of aqueous 

 humor (or even of water), cover, examine with a high 

 power. 



To make a permanent preparation of the vibratile 

 cells, rapidly separate the material obtained by scraping 

 the pharyngeal wall, expose for 10 minutes to osmic 

 acid vapor, stain in picro-carmine. 



The tonsils should be studied by the method described 

 for lymphatic glands. 



The ossophagus. — As man's oesophagus can seldom be 

 had sufficiently fresh to make good preparations, select 

 that of the dog, rabbit or rat. Slit open the organ, cut 

 out a piece and spread it in a saucer of very strong al- 

 cohol for 24 hours; harden in gum and alcohol. Make 

 transverse and longitudinal sections. Stain in picro- 

 carmine : mount in glycerine with a little picro-car- 

 mine. 



