60 CHAPTER V. 



several hours, wash out with water, treat the tissues in bulk, or the sections 

 with alcohol containing tincture of iodine. 



TELLYESNICZKY (Arch.f. inik. Anat., Hi, 2, 1898, p. 238), who has lately 

 tried this fluid on testes of Salamandra, writes that for accurate preserva- 

 tion of cell-structures it is comparable to liquid of FLEMMLNG, with the 

 advantage of better penetration (therefore applicability to larger pieces of 

 material), absence of over-fixation of superficial layers, easier staining, and 

 cheapness. He thinks the sodium sulphate may be omitted from it with- 

 out any change in the results. Numerous recent authors speak very highly 

 of this reagent. 



75. Foi's Mixture (Quart. Journ. Mic. Sci., 1895, p. 287 ; Journ. Roy. 

 Mic. Soc., 1895, p. 486). Equal parts of saturated solution of sublimate 

 in normal salt solution, and of liquid of Miiller, or 5 per cent, solution of 

 bichromate. 



Very much like Zenker's mixture, with the acetic acid omitted, which 

 appears to me to be certainly for most purposes a false step. 



76. Chromo-nitric Sublimate (ROSENSTADT, Arch. f. mik. Anat., 

 xlvii, 1896, p. 748). Three volumes of saturated aqueous sublimate solution 

 with 1 volume of liquid of PERENYI. 



77. Chloride of Platinum (Platinic Chloride, PtCl 4 ). A 

 reagent, originally introduced for the study of karyokinesis, 

 but of general application. RABL, to whom we owe the 

 introduction ot this agent, employed an aqueous solution of 

 1'300. The objects remained in it for twenty-four hours, 

 and were then washed with water, hardened in alcohol, and 

 sectioned. 



Rabl found it give better results (for the study of karyo- 

 kinesrs) than any other reagent except chromoformic acid 

 (^ 41). It causes a slight shrinkage of the chromatiii ele- 

 ments, a condition that renders the granules of Pfitzner and 

 the longitudinal division of the elements very distinctly 

 visible (see Kabl's paper in Morph. Jahrl., Bd. x, 1884, p. 

 216). 



Platinum chloride is an extremely deliquescent salt, and 

 for this reason had better be procured in solution. Ten per 

 cent, solutions ;nv found in commerce. 



For the platinic mixtures see ante 49, 50,53, also EABL'S 

 mix tun,', under E mbryological Methods. For the platinic 

 t'ormol of MODIN, see Arch. d'Anat, Micro m-., ii, 4, 1899, p. 

 423. 



