FIXING AND HARDENING AGENTS. ' 59 



water, 2 vols. Embryos may be left in it for twelve hours, 

 washed for two hours in water, and brought into weak 

 alcohol. 



MANN'S (op. cit., xi, 4, 1895, p. 480). 1 per cent, of picric acid with or 

 without 1 per cent, of tannin in a saturated solution of sublimate in normal 

 salt solution. 



The same author's Alcoholic Picro-sublimate (Anat. Am., 8, 1893, 

 pp. 441 443) consists of absolute alcohol 100 c.c., picric acid 4 grms., 

 sublimate 15 grms., tannin 6 to 8 grms. The tannin is added in order to 

 prevent excessive hardening. 



TELLYESNICZKY (Arch. f. mik. Anat., lii, 1898, p 237) says of Mann's 

 tannin liquid, " its action is an entirely destructive one." 



O. vom RATB'S Picro-sublimate (Anat. Anz., xi, 9, 1895, 

 p. 286). Cold saturated solution of picric acid, 1 part; hot 

 saturated solution of sublimate, 1 part ; glacial acetic acid, | 

 to 1 per cent. Fix for several hours and bring direct into 

 alcohol . 



The same author's Picro-sublhnate-osmic Mixture (loc. cit.) 

 consists of the above with the addition of 10 per cent, of 2 

 per cent, osmic acid solution. 



72. Osmio-sublimate Mixtures. MANX'S (Zeit. f. wiss. Milt., 

 xi, 4, 1894, p. 481) consists of a freshly-prepared mixture 

 of equal parts of 1 per cent, osmic acid solution and saturated 

 solution of sublimate in normal salt solution (for nerve- 

 centres) . 



For APATHY'S see 358. 



DRUNER'S (Jena. Zeit. Naturw., xxviii, 1894, p. 294) con- 

 sists of 1 part of 1 per cent, osmic acid solution added to 20 

 parts of a solution of 5 per cent, each of sublimate and 

 glacial acetic acid in water. 



O. vom RATH'S, see last . 



73. Chromo-sublimate. Lo BIANCO (Mitth. Zool. Stat. 

 Neapel, ix, 3, 1890, p. 443). Concentrated sublimate solu- 

 tion, 100 parts, 1 per cent, chromic acid, 50 parts. 



74. ZEXKER'S Mixture (Milnchener med. Wochenschr., 24, 1894, p. 534 ; 

 quoted from MERCIER, Zeit. f. wiss. Mik., xi, 4, 1894, p. 471, where will be 

 found minute instructions for using it). Five per cent, of sublimate and 

 o per cent, of glacial acetic atid, dissolved in solution of MULLER. Fix for 



