GENERAL STAINS. 397 



dark ; then imbedded, either in paraffin or celloidin, and cut. The sections, 

 after removal of the paraffin (if that have been used), are treated with 

 alcohol, and then with water. They are stained for a quarter or half an 

 hour in a well-ripened mixture of 1 part of hsematoxylin, 30 parts of 

 alcohol, 1 part of ammonia alum, and 300 parts of water (or they may be 

 treated for a quarter of an hour to an hour with saturated solution of car- 

 bonate of lithia, and then for an hour, in total darkness, with simple satu- 

 rated aqueous solution of haematoxylin). After staining to a deep black 

 they are rinsed in water and differentiated until .they turn red (a quarter of 

 an hour at most), either in 70 per cent, alcohol acidified with 0'5 .to 1 per 

 cent, of hydrochloric acid or in a solution containing 0'5 part of oxalic acid, 

 O'l to 0'25 of hyposulphite of soda, and 100 of water. They are then 

 washed with pure water until they turn blue or bluish grey ; after which 

 they may either be mounted, or first counterstained by momentary immer- 

 sion in a strong solution of neutral carmine. If desired, sections after 

 staining may be differentiated in Weigert's borax-ferricyanide liquid, instead 

 of the liquids here given. 



756. Alizarin has been recommended by BENCZUE (see THANHOFFEE'S 

 Das MikrosJcop; or Zeit. f. wiss. Mik., 1884, p. 97). It is directed that 

 sections be stained for twenty-four hours in a concentrated solution of 

 alizarin in alcohol. 



Anilin blue alone is useful for the demonstration of ganglion-cell pro- 

 cesses (see ZUPPINGEB, in Arch,/, mik. Anat., 1874, p. 255). 



757. Anilin blue-black was first recommended by SANKEY 

 (Quart. Journ.Mic. Sci., 1876, p. 69). He stained in a 0'5 

 per cent, solution, and, in order to obtain a differential stain, 

 washed out for twenty to thirty minutes in solution of chloral 

 hydrate. BEVAN LEWIS (Human Brain, p. 125) considers this 

 to be one of the most valuable stains for nervous centres. He 

 stains sections for an hour in O25 per cent, aqueous solution, 

 and clears and mounts (in the case of brain or cord sections) ; 

 for the cortex of the cerebellum he washes out for twenty to 

 thirty minutes in 2 per cent, chloral solution. SANKEY and 

 STIELING have also used anilin blue-black in a much weaker 

 solution, which Bevan Lewis does not recommend. YEJAS, 

 however (Arch. f. Psychiatrie, xvi, p. 200), obtained good 

 results by staining from eighteen to twenty-four hours in a 

 solution of 1 in 3000. 



GIEEKE (Zeit. f. wiss. Mik., 1884, p. 379) was not able to 

 obtain good results with anilin black procured in Germany, 

 and finds that the treatment with chloral is injurious to the 

 preservation of the tissues. MAETINOTTI (ibid., p. 478) comes 

 to the same conclusion. 



LUYS (Gaz. med. de Paris, 1876, p. 346) greatly recommends 



