EXAMINATION AND PRESERVATION MEDIA. 273 



Mix, agitate, filter, and preserve in a cool place. Eecom- 

 inended for the study of red blood-corpuscles and ciliated 

 cells. 



405. PACIXI'S Fluids (Journ. de Mic., iv, 1880; Journ. Boy. Mic. Soc., 



[N. S.], ii, 1882, p. 702, and previous editions of this work). Antiquated 

 and superfluous. They consist essentially of corrosive sublimate of from 

 one half to one third per cent, strength, with the addition of a little salt 

 or acetic acid. 



406. GOADBY'S Fluids (Micro. Diet., art. " Preservation," or previous 

 editions of this work). Quite unsuited for histological purposes. 



Other Fluids. 



407. Chloride and Acetate of Copper (RIPART et PETIT'S fluid, 

 Brebissonia, 1880, p. 92; CARNOY'S Biol. cell., p. 95). 



Camphor water (not saturated) . 75 grms. 

 Distilled water . . . .75 



Crystallised acetic acid ... 1 grm. 

 Acetate of copper . . . 0*30 



Chloride of copper . . . 0'30 ,, 



A valuable medium for work with delicate fresh tissues. 

 It may be used in combination with methyl green, which it 

 does not precipitate. The addition of a drop of osrnic acid 

 or corrosive sublimate does not cause the least turbidity, and 

 enhances its fixing action. 



408. Tannin (CAENOY, loc. cit.). 



Water ..... 100 grms. 



Powdered tannin .... 0'40 grm. 



As an examination medium only. 



409. Methyl Green. See 277. The aqueous solution is 

 very useful as an examination medium for fresh tissues. It 

 should be taken fairly concentrated, in which state it has 

 sufficient fixing power, which is enhanced by the addition of 

 a trace of osmic acid. 



410. WICKEBSHEIMEB'S Fluid (Zool. Anz., 1879, p. 670; cf. Journ. 

 Roy. Mic. Soc., 1882, p. 427; id., 1880, p. 355; and Entomol. Nachr., 



1880, p. 129). Worthless for histological purposes. 



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