130 COMBINATION STRAINS. 



parts of absolute alcohol with one part of aqueous solution of 

 eosin (0'5 per cent.), wash, and stain for five minutes in 0*5 

 per cent, aqueous solution of methyl green. Wash, dehydrate, 

 clear, and mount in balsam. The preparations do not keep 

 well in glycerin. 



The method may be varied (1. c., p. 150) by diluting the 

 methyl green solution with 50 volumes of water, and staining 

 for twenty- four hours. 



It may also be varied by diluting the original methyl green 

 solution with 3 volumes of absolute alcohol. 



The preparations should not be left in the alcohol used for 

 dehydrating after the colour of the eosin has begun to re- 

 appear. 



252. Methyl Green, Orange, and Saurefuchsin (BIONDI and 

 HEIDENHAIN, Pfliiger's Arch., xlii, 1888, p. 1 ; Zeit. f. wiss. Mik., v, 4, 

 1888, p. 520). To 100 c.c. saturated aqueous solution of orange add with 

 continual agitation 20 c.c. saturated aqueous solution of Saurefuchsin and 

 50 c.c. of a like solution of methyl green. 



Dilute the mixture with 60 to 100 volumes of water. The dilute solution 

 ought to redden if acetic acid be added to it ; and if a drop be placed on 

 blotting paper it should form a spot bluish-green in the centre, orange at 

 the periphery. If the orange zone is surrounded by a broader red zone, the 

 mixture contains too much fuchsin. 



Stain (sublimate sections) for six to twenty-four hours. Wash out with 

 alcohol, clear with xylol, and mount in xylol balsam. 



253. Methyl Green and Bismarck Brown (LIST, Zeit. f. iviss. 

 Mik., ii, 1885, p. 145). Stain for a few minutes in Weigert's 

 Bismarck brown ( 106), wash, and stain in 0*5 per cent, 

 aqueous solution of methyl green. Clear with bergamot oil 

 or xylol, and mount in balsam. 



Or, dilute the Bismarck brown for staining with 3 volumes 

 of absolute alcohol, wash out with strong alcohol, and stain for 

 a few minutes in the methyl green solution diluted with 3 

 volumes of absolute alcohol. 



Or, stain for twenty-four hours in the Bismarck brown solu- 

 tion diluted with 50 volumes of water, and then for twenty- 

 four hours in the methyl green solution diluted with 50 

 volumes of water. 



254. Methyl Green and Nitrate of Rosanilin (LIST, I. c.). 

 Stain for a few minutes in 0*5 per cent, aqueous solution <>F 

 methyl green, wash, and stain (L c., iii, 1886, p. 393) for ten 



