NERVOUS SYSTEM — CYTOLOGICAL METHODS. 405 



For feii'pheral nerves, GtOLGI [tbiil., p. 288) puts pieces 

 into the bichromate for from four hours to at most two 

 days, passing specimens at intervals into the silver, where 

 they remain for twelve to twenty-four hours. Wash in 

 several changes of alcohol, tease therein, and pass through 

 oil of turpentine into damar. Reduce therein in direct sun- 

 light for a few days or weeks. The preparations keep well. 



He also {ihiiJ., p. 238) puts pieces into a mixture of 10 

 parts 2 per cent, bichromate with 2 of 1 per cent, osraic acid, 

 and passes them on into the silver at intervals of three hours, 

 after the first four, during twenty-four hours. The silver is 

 of 0'5 per cent, strength, and the pieces remain in it for 

 any time not less than eight hours. The rest as before. 

 Results somewhat more precise, but the stain does not keep 

 in damar. It is important that the nerve should not have 

 been ulrelched. 



Sala {Verh. Anat. Ges., 1900, p. 176) employs the method 

 of Veeatji for the intracellular network, last §. 



See also concerning these methods Mondino, 0]j. cit., viii, 

 p. 45, and Petrone, Intern. Monatasclir. Anal., v, 1888. 



GrALLi (Zelt. wifis. Mik., iii, 188G, p. 467) puts for eighteen 

 to twenty days into solution of Miiller, then stains for fifteen 

 to twenty minutes in aqueous solution of China blue, washes 

 out in alcohol, clears in essence of turpentine, and mounts in 

 damar. 



Plainer [Zeit. wins. Mik., vi, 1889, p. 186) fixes for 

 several days in a mixture of 1 part of Liq. Ferri Perchlor. 

 (Ph. G., ed. 2) and ;i to 4 parts of water or alcohol, washes 

 out well in water and stains for several days or weeks in a 

 concentrated solution of " Bclitgriin " in 75 per cent, 

 alcohol. See also Beer, Jahrh. Psychiatrie, ii, 1893, 1 Heft. 



Cox {Anal. Hefle, i, 1898, p. 75) fixes nerves in osmic acid 

 of 2 per cent, (rabbit) or 1 per cent, (frog), washes, de- 

 hydrates, clears with bergamot oil, and mounts in balsam. 

 The bergamot oil dissolves out the myelin, and leaves the 

 neuroceratin visible. It may be necessary to leave the 

 nerves for forty-eight hours in the oil. 



CoENiKG {Auat. Anz., xvii, 1900, p. 309) studies the net- 

 work in the ischiatic of the frog on sections of sublimate 

 material strongly stained with iron hsematoxylin. 



See also Kaplan {Arch. I'.sychiatr., xxxv, 1902, jj. 825 ; 



