436 CHAPTER XXXI \'. 



centrated metliylen blue into the body-cavity of Fishes, 

 removes the brain after lialf an hour, puts slices of it into 

 the same solution for half an hour, and fixes as usual. 



Lennhoff [Neurol. Zentralb., 1910, p. 1) has some com- 

 plicated methods with polychrome metliylen blue and 

 suljjho-cyanide of potassium, or ferricyanide. 



834. Lennhoff's Iron Method {ibid.). — Sections put for 

 thirty seconds into 2 c.c. of 15 per cent, solution of tannin 

 with 3 drops of 5 per cent, solution of oxalic acid, rinsed in 

 water, then for a few seconds in 1 per cent, solution of 

 chloride of iron till no further blackening occurs, then 

 washed, dehydrated and mounted in balsam. Axis cylinders 

 black, cells grey. 



836. Fajfestajjj's Hsematoxylin {Polii. Arch. Biol. Med. 

 Wiss., i, 1901, p. 189). — Sections by the freezing method of 

 material fixed for two to seven days in formol of 5 to 10 

 per cent, mordanted for five to twenty-four hours in chromic 

 acid of 0'25 to 0'5 per cent., well washed, stained for twenty- 

 four hours in 1 per cent, aqueous hasmatoxylin, and differen- 

 tiated by the method of Pal. 



Other Methods. 



836. Nabias (C. B. Soc. Biol, Ivi, 1904, p. 426) treats 

 sections until yellow with solution of 1 grm. iodine and 

 2 grnis. iodide of potassium in 300 of water, washes, treats for 

 a few minutes with 1 per cent, chloride of gold, washes and 

 reduces in anilin or i-esorcin in water (1 : 100, or less for the 

 latter) and mounts in balsam. 



Afathy's Gold Method has been given § 371. 



Gbklach's Bichromate and Gold Proeets has been given. § 369. 



For a complicated Gold Method of Ramon y Cajal, see Bcv. trim. 

 Mtci:, V, liKlO, p. 95 ; or Zeit. ivhs. Mile, xix, 190:2, p. 187. 



For Upson's exceedingly complicated Gold and Iron and Vana- 

 dium Methods see Mekcibk, in Ze/'t. xviss. Mil;., vii, 1891. p. 474; or in 

 his Coupes da Syst'cme Ncrwux Central, p. 231; or curly editions. 



For Fajjsbstajn's complicated Silver Method see JV^eitcoL Ccntralb., 

 XX, 1901, p. 98 ; or Zeit. 'wi.<s. Mile, xviii, 1901, p. 214. 



Maqini's Zinc Chloride Process (see Boll. Accad. Med. di Soma, 

 1886; Zeit. wiss. Mih., 1888, p. 87, or early ediiiotis). 



