APPENDIX 



A. — List of Eeagents, etc. 



1. Acetic Acid. 



Use. — Clears opaque tissues and thick sections ; swells 

 cellulose -walls and starch grains ; dissolves crystals of 

 calcium carbonate witli effervescence. Dilute solutions 

 bring out nuclei very clearly. 



Preparation. — To prepare the dilute, or one per cent, aque- 

 ous solution, dissolve one gram of glacial acetic acid in 

 ninety-nine cubic centimetres of distilled water. 



2. Acetic Acid Carmine [Schneider^ s). 



Use. — Stains fresh tissues rapidly ; makes the nucleus show 

 plainly. 



Preparation. — From glacial acetic acid prepare a solution 

 of forty-five per cent, strength. Heat this solution to 

 the boiling-point, and while at this temperature add 

 finely pulverized carmine until no more will dissolve. 

 Filter the mixture and use it concentrated, or, better, 

 diluted to one per cent. The latter strength stains more 

 slowly than the former. 



.3. Alcohol. 



jjse_ — Of all reagents alcohol is used most frequently, and 

 in the largest amount. It is not only a hardening agent 

 and a preservative for permanent preparations, but in 

 the diluted form is used in the examination of preserved 

 specimens ; consequently, a large supply should be kept 



