and Laboratory Methods. 2043 



in 100 grams of absolute alcohol. Just before use 1 part of this solution is 

 mixed with 2 parts of a one-half per cent, solution of ammonia alum. 



Rees (1901) recommends Delafield's haematoxylin or Mayer's haemalum for 

 staining malarial blood. 



4. Methylen Blue. 



This is the most important basic stain that we have for staining the blood. 

 It is a precise basic stain, staining only the basophile elements, and does not 

 overstain. It forms the basic part of the modern eosin-methylen blue stain for 

 the blood. 



A Cojicentrated Watery Solution of methylen blue stains all of the basophile 

 elements of the blood except the granules of the mast cells. 



Loffler's Alkali7ie Methylen Bhce solution is a better blood stain than the 

 watery solution. It is especially recommended for staining bacteria, malarial 

 parasites and the basophile cytoplasm or granules of red blood corpuscles. The 

 formula is as follows : 



Concentrated alcoholic solution of methlylen blue, - 30 c. c. 



Caustic potash in 1:10,000 solution, - - . . 100 c. c. 



Preparations which are best fixed in equal volumes of absolute alcohol and 



ether should be stained from one to five minutes or more. It does not overstain. 



The stained preparations are washed off with water and may either be examined 



directly in water or dried and mounted in balsam. 



SahWs Borax Methylen Blue solution is recommended by Malachowsky 



(1891) for staining malarial parasites of the blood. Dry preparations are fixed 



in absolute alcohol for several minutes and then stained for twenty-four hours in : 



Concentrated watery solution of methylen blue, - 24 



5 per cent, solution of borax, - . - - 16 



Water, 40 



Filter after twenty-four hours. 

 Rees (1901) gives another formula : 



Pure medicinal methylen blue, - - - 2 per cent. 

 Borax, --..... 5 per cent. 



Distilled water, ------ 93 per cent. 



Mix. Filter before use. Stain thirty to fifty seconds. The stain improves 

 by keeping. 



5. Methyl Green. 



Arnold and Hozvell (\%^V) recommend methyl green in 0.6 per cent, sodium 

 chloride for staining the nuclei and nuclear division in fresh blood. The blood 

 cells are fixed as well as stained by this solution. 



6. Methyl Green and Fuchsin. 



Ehrlich recommends the following double basic stain : A saturated watery 

 solution of methyl green is mixed with an alcohol solution of fuchsin. This 

 stain requires only slight fixation and only a few minutes' action. Nuclei are 

 stained green, red corpuscles red (diffuse), protoplasm of lymphocytes fuchsin 

 color. It is especially recommended for demonstrating lymphatic leukaemia. 



