54 METHODS OP MICROSCOPICAL RESEARCH. 



Water. 



Squamous epithelium may be stained in magenta 

 solution and examined in water. To obtain it, 

 scrape the inside of the cheek with a blunt knife. 

 The surface of the cheek may be also scraped and 

 the scraping examined in water and afterwards 

 irrigated with a 5 per cent, solution of liquor 

 potassae. 



Dilute Alcohol. 



Mix two parts of water with one of rectified 

 spirit. This is a useful dissociating solution recom- 

 mended by Ranvier. 



Olfactory, ciliated and transitional epithelium, 

 may be prepared as permanent preparations thus : 

 Place a small piece of fresh trachea of a small quad- 

 ruped for ciliated a piece of fresh bladder for 

 transitional the head of a frog, with the nostrils 

 slit up, for olfactory epithelium, in the solution for 

 two days. The parts are then scraped and the 

 scrapings stained and mounted in glycerine, or 

 glycerine jelly. Stirling " fixes " the ciliated 

 epithelium by placing the scraping in a 1 per cent, 

 solution of osmic acid. Non-striped muscle may 

 be obtained by taking out the bladder of a fresh- 

 killed frog and distending it with the solution, then 

 placing it for twenty-four hours in the solution. 

 After brushing away the mucous membrane with a 

 camel-hair brush, stain the bladder in picro- 

 carmine, and mount a piece in Farrant's medium. 

 Isolated heart muscle fibres of the frog's and mam- 

 malian heart can be obtained by the same process. 



