INTKODUCTION. 



4^ 



desired, with a 1 per cent, solution of eosin or orange G. 

 Dehydrate by bringing through graded alcohols to absolute 

 alcohol. Clear in xylol. Mount in Canada balsam. 



DobelVs Iron Hsematein. — Fix in Schaudinn's fluid. Bring 

 down through 30 per cent, and 10 per cent, alcohol to distilled 

 water. After washing, bring up through various grades of 

 alcohol to 70 per cent., and from that transfer to 1 per cent, 

 solution of iron alum in 70 per cent, alcohol for 10 minutes 

 (the solution is made by dissolving 1 grm. iron alum in 23 c.c. 

 warm distilled water and adding 77 c.c. of 90 per cent, alcohol). 

 Rinse in 70 per cent, alcohol. Stain in 1 per cent, solution 

 of hsematein in 70 per cent, alcohol for 10 minutes. Rinse 

 in 70 per cent, alcohol. Differentiate films in original alum 

 solution and sections in 70 per cent, acid alcohol. Wash in 

 several changes of 70 per cent, alcohol. Dehydrate ; clear ; 

 mount. The whole process may be carried out in 30 minutes. 

 Light green in 90 per cent, alcohol may be used as a counter- 

 stain. 



Mayer's Hssmalum. — To prepare the stain dissolve 1 grm. 

 of haematin in 50 c.c. of 90 per cent, alcohol, dissolve 50 grms. 

 of alum in 1000 c.c. of water, and mix up the two solutions. 

 Keep a crystal of thymol in the bottle to prevent growth 

 of fungi, etc. 



When using the stain, add a few drops of the stain to a Petri 

 dish of distilled water, and leave the films in for several hours 

 or overnight. Wash the films in running tap -water till they 

 are quite blue. Dehydrate by bringing up though various 

 grades of alcohol to absolute alcohol. Clear in xylol and 

 mount in Canada balsam. 



Mayer's Acid Hsemalum. — This strain is prepared from 

 Mayer's hsemalum by adding acetic acid to a strength of 

 2 per cent. It is used in the same manner, but has less 

 tendency to overstain. 



If overstaining occurs with either of the above stains, 

 place the films in acid alcohol. After they are decolorized, 

 wash the films well in running water till the acid is completely 

 neutrahzed and they are blue. 



Mallory's Eosin and Methylene Blue. — This is recommended 

 for sections of tissues containing parasites. Fix in Zenker's 

 fluid. Wash out the fixative in rumiing water for several 

 hours. Stain in warm 5 per cent, aqueous solution of eosin 

 for 20 minutes or longer, wash in water, and stain in Unna's 

 alkahne methylene-blue solution diluted with 4 or 5 parts of 

 water for 10 to 15 minutes. Wash in water, diffierentiate in 

 95 per cent, alcohol, controlling under a microscope, until 

 sections are pinkish but nuclei deep blue. Dehydrate quickly 

 and mount. 



Mallory's Triple Stain. — ^This is also recommended for 



