METHODS FOR INVERTEBRATES. 481 



Trypanosomes intra vitam by adding a drop of concentrated 

 solution o neutral red to the edge of a drop of blood spread 

 between slide and cover, 



925. Flagellata. LAUTERBORN (Zeit. witss. ZooL, lix, 1895, 

 p. 170) fixes Geratium for about ten minutes in liquid of 

 Plemmingj puts into alcohol for twenty-four hours, brings 

 back into water, bleaches if necessary with hydrogen per- 

 oxide, and stains with picrocarmine or Delafield's hsematoxylin. 

 He also imbeds in paraffin, 921, and stains sections with 

 iron hasmatoxylin. 



ZACHARIAS (ZooL Anz., xxii, 1899, p. 72) fixes Uroglena, 

 etc., with a mixture of 2 vols. saturated aqueous solution of 

 boracic acid and 3 of saturated sublimate. 



926. Stains for Flagella. The ROMANOWSKY stain will give 

 a red stain of the flagella of some forms. 



The method of LOFFLER (Centralbl. BakterioL, vi, 1889, p. 

 209 ; vii, 1890, p. 625 ; Zeit. wise. Mik., vi, 1889, p. 359 ; vii, 

 3, 1890, p. 368; Journ. Roy. Mic. Soc., 1889, p. 711; 1890, 

 p. 678) is as follows. To 10 c.c. of a 20 per cent, solution 

 of tannin are added 5 c.c. of cold saturated solution of ferrous 

 sulphate and 1 c.c. of (either aqueous or alcoholic) solution 

 of fuchsin, methyl violet, or " Wollschwarz." Cover-glass 

 preparations are made and fixed in a flame in the usual way, 

 special care being taken not to over-heat. Whilst still warm 

 the preparation is treated with mordant (i. e. the above-des- 

 cribed mixture), and is heated for half a minute, until the 

 liquid begins to vaporise, after which it is washed in distilled 

 water and then in alcohol. It is then treated in a similar 

 manner with the stain, which consists of a saturated solution 

 of f uchsin in anilin water (p. 177), the solution being pre- 

 ferably neutralised to the point of precipitation by cautious 

 addition of O'l per cent, soda solution. 



See also LIEBETANZ, Arch. Protistenk., xix, 1910, p. 23. 



BUNGE (Journ. l\oy. Mic. Soc., 1894, p. 640; Zdt. wiss. Mik., 

 xiii, 1896, p. 96) makes the mordant by mixing three parts 

 of the tannin solution with I of liquor ferri sesquichlorati 

 diluted twentyfold with water, and lets the mixture ripen 

 for some days exposed to the air, or (Journ., 1895, pp. 129, 

 248) adds to it a few drops of hydrogen peroxide, until it 



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