1895.] MICROSCOPICAL JOURNAL. 239 



mucous membrane measuring about 1 c. in the i alcohol. 

 In twenty-four hours scrape the surface and spread the 

 result in a drop of the i alcohol ; stain with picro-car- 

 mine and cover after partly drying-. After examining 

 the cells in the staining fluid, let glycerine run under 

 the cover so as to penetrate the cells very slowly. 



/Sections. — After fixing by osmic acid (1 per cent) 

 1 mm. square of the mucous membrane, in 24hours wash 

 carefully (12 hours), harden in gum and alcohol, section, 

 stain in alum carmine, mount in glycerine. 



THE LARYNX. 



This presents a frame-work, ligaments, muscles and 

 a mucous membrane. The study of the frame-work 

 needs no other technique than that described for cartil- 

 aginous tissue. The same may be said of the muscles 

 and the ligaments. The mucous membrane will there- 

 fore exclusively occu[)y us. 



Take the membrane from the pharynx of an animal 

 just killed; do not allow it to dry. If the larynx of a 

 man can be obtained in half an hour or even one hour 

 after death, do not allow the opportunity to escape, as 

 the mucous membrane is a most remarkable object for 

 study. 



Dissociation of the epithelial cells may be accomplished 

 after maceration in the :i alcohol, following the tech- 

 nique described for the olfactory epithelium. 



Sections. — Make them perpendicular to the surface. 

 For a fixative use alcohol, osmic acid or ammonia bi- 

 chromate. Harden in gum and alcohol, stain in ahim 

 carmine if osmic acid is used, picro-carmine after alco- 

 hol and ha'matoxylin after bichromate. 



For the study of the trachea and the bronchia use the 

 preceding methods. 



(To he continued). 



