462 CHAPTEll XXXVJ. 



cotised by adding to the water at intervals a few drops of the 

 following mixture: 



Hydrochlorate of cocaine 2 per cent, solution . 3 parts. 



Methylated spirit . . . . . . 1 „ 



Water & „ 



As soon as the cilia have ceased to beat^ or are seen to be 

 on the point of ceasing to beat, they are fixed by adding a 

 drop of liquid of Flemming or of { per cent, osmic acid. 

 After half a minute or less the animals are taken out with a 

 pipette^ and thoroughly washed by passing them through two 

 or three watch glasses of distilled water. They are then 

 definitely mounted in a mixture of formol 2| parts, distilled 

 water 37^ parts. 



ZoQRAF [Coniptes Bend., cxxiv, 1897, p. 245) narcotises as 

 RoDSSELET, but without the spirit, fixes with osmic acid for 

 two to four minutes, then replaces this by i-aw pj'roligneous 

 acid diluted with eight to ten volumes of water, and after 

 five to ten minutes washes in several changes of water, and 

 passes through successive alcohols into glycerin or balsam. 



Lenssen [La Cellule, xiv, 1898, p. 428) for the embryology 

 of Hydatina, kills with hot saturated sublimate, dehydrates, 

 stains lightly, imbeds in paraffin and stains with hsemalum. 



HiHSCHPEi.DEE (op. cit. supra) narcotises with cocaine, and 

 fixes with Fol's picro-ohromic acid. 



Beauchamp [Arch. Zool. Exper., iv, 1906, p. 29) finds 1 per 

 cent, stovaine better than cocaine for some forms. He {ibid., 

 X, 1909, p. 77) fixes for five to ten minutes in four parts of 

 1 per cent, osmic acid with one of 6 per cent, sublimate and 

 five of 5 per cent, bichromate of potash, and one drop of acetic 

 acid for each 2 c.c, and imbeds in celloidin, and then through 

 chloroform in paraffin (three to ten minutes). 



See also Tozek [Journ. Roy. Micr. Soc, 1909, p. 24). 



887. Acanthocephali. — Saeeftigen {Murph. Jahrb., x, 1884, 

 p. 120) obtained the best results by killing gradually with 

 O'l per cent, osmic acid; the animals placed in this contract 

 dui'ing the first hours, but stretch out again and die fully 

 extended. Similarly with O'l per cent, chromic acid; Echino- 

 rhynci live for days in it, but eventually die fully extended. 



Hamann {.Ten. Zeit., xxv, 1890,p. 113) has succeeded with sub- 

 limate, and also with alcohol containing a little platinum chloride. 



