SECTION THREE 



VENETIAN TURPENTINE 

 For mounting filamentous algae and other delicate material 



Solutions required: 



A. Glycerin 5%. 



B. Venetian turpentine 10% in abso- 

 lute alcohol. 



Technique: 



1. Stain the material in suitable aqueous stains. 



2. Transfer to Solution A, and leave therein for several days in 

 an open dish. 



3. Wash with several changes of 95% alcohol. 



4. Wash with two or three changes of absolute alcohol. 



5. Transfer the material quickly from absolute alcohol to 

 Solution B (10% Venetian turpentine in absolute alcohol), in an 

 open dish. 



6. Place the dish with contents over soda lime in a desiccator 

 for several days until the fluid becomes viscous. 



7. Mount on slides. 



ADHESrVES, CEMENTS, IMMERSION OILS AND 

 MISCELLANEOUS REAGENTS 



CARBOCHROME INK 



This consists of a stable colloidal suspension of finely divided 

 carbon in distilled water, and is employed for injection, for 

 which purpose the ink is usually diluted to about one-fifth its 

 standard strength. Unlike Indian ink, it does not contain gum 

 and other substances necessary to preserve gummy solutions 

 which are subject to attack and decomposition by air-borne micro- 

 organisms. Carbochrome ink, diluted to suitable proportions for 

 the particular class of animal, is non-toxic to laboratory animals, 

 except the guinea pig, which is adversely affected by carbon 

 injections. It is not only more suitable for injection than Indian 



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