SCHWALBB'S METHODS. 307 



646. Sections. Perhaps the majority of recent workers re- 

 commend celloidin ; but I see no reason for not employing 

 paraffin. Sections may be mounted in dammar, or (FLEMMING) 

 in glycerin. RAMON Y CAJAL (1. c., last ) mounts in dammar 

 or colophonium varnish, without a cover-glass. 



647. Dissociation Methods. For maceration preparations 

 you may use weak solutions (O2 to O5 per cent.) of osmic 

 acid, for fixation, and then macerate in 0*02 per cent, chromic 

 acid (M. SCHULTZE), or in iodised serum (M. SCHULTZE), or in 

 dilute alcohol (LANDOLT), or in Muller's solution, or (RANVIER, 

 Traite, p. 957) in pure water, for two or three days. THIN 

 (Journ. of Anat., 1879, p. 139) obtained very good results by 

 fixing for thirty-six to forty-eight hours in one-third alcohol, 

 or in 25 per cent, alcohol, and then staining and teasing. 



SCHIEFFERDECKER (1. c., 644) macerates fresh retina for 

 several days in the methyl mixture, 520. 



KRAUSE (Intern. Monatsch.f. Anat. u. Hist., 1884, p. 225; 

 Zeit. f. wiss. Mik., 1885, pp. 140, 396) recommends treatment 

 for several days with 10 per cent, chloral hydrate solution. 

 Barrett finds that this process preserves the rods and cones 

 admirably. 



Inner Ear. 



648. Schwalbe's Methods (Beitr. z. Phys., 1887 ; Zeit. f. wiss. 

 Mik. t iv, 1, 1887, p. 90; Journ. Roy. Mic. Soc., 1887, p. 840). 



Fix (cochlea of guinea-pig) for eight to ten hours in 

 f< Flemming" wash in water, decalcify (twenty-four hours is 

 enough) in 1 per cent, hydrochloric acid, wash the acid out, 

 , ;ind imbed in paraffin. 



649. Other Methods. WALDEYER, Strieker's Handb., p. 958 (decalcifi- 

 cation either in <HM)1 per cent, palladium chloride, containing 10 percent. 

 of 1IC1, or in chromic acid of (>25 to 1 per cent.). 



KUBAN PRITCHARD (Journ. Roy. Mic. Soc., 1876, p. 211). (Decalcifica- 

 tion in 1 per cent. nitric acid). 



LAVDOWSKV (Arch. f. mile. Anat., 1876, p. 497). Fresh tissues (from the 

 cochlea) arc treated with 1 per cent, solution of silver nitrate, then washed 

 for tfii minutes in water containing a few drops of 0*5 or 1 per cent, osmic 

 acid solution, and mounted in glycerin. 



MAX FLESCH (Arch.f. mik. Anat., 1878, p. 300). 



TAFANI (Arch. Hal. de Biol, vi, p. 207). 



