NEUROGLIA AND SENSE ORGANS 545 



(c) '" Fuchsin-light green " Method. Fix for twenty-four hours 

 in formalin, and thence transfer direct to Flemming's solution 

 for eight days. Wash twelve to twenty-four hours and imbed in 

 paraffin of 58° C. melting-point. Cut very thin sections (2 to 'Sfi), 

 dry, remove j>araffin and wash with 96 per cent, alcohol. Thence 

 place in paraffin oven at 58° C. for one hour in a saturated watery 

 solution of acid fuchsin. Wash twice with water till no more 

 stain is given off, and differentiate for ten to twenty seconds in 

 a mixture of 30 parts of saturated alcoholic picric acid and 60 

 parts of distilled water. Wash twice thoroughly in water and 

 stain for twenty to fifty minutes in a half-saturated watery solu- 

 tion of light green. Wash quickly, first in water and then in 

 96 per cent, alcohol, absolute alcohol, xylol, balsam. (This method 

 does not differentiate the neuroglia fibres, but gives a very com- 

 plete picture of the structure of the supporting tissues. It also 

 brings out sharply " fuchsinophil " and lipoid granules in the 

 neuroglia cells.) Bertkand and Hadjioloff (Rev. Neurol., ii, 

 1927, 34, p. 752), stain with Ziehl's earbol-fuchsin on a hot plate 

 and after washing the sections in distilled water until no more 

 stain is given off they then stain with a saturated aqueous solution 

 of light green for seven to fifteen minutes on a hot plate. 



1092. Other Methods for Granules, etc. Alzheimer (lac. cit.) 

 also stains fuchsitiophil granules by treating Flemming fixed 

 paraffin sections (see above) first for one hour at 37° C. in a 

 saturated watery solution of copper acetate, and after two washes 

 in distilled water, staining for half an hour in 10 per cent, alcoholic 

 hsematoxylin, 10 c.c. distilled water, 87 c.c. saturated lithium 

 carbonate solution 3 c.c. Wash rapidly in water, alcohol, xylol, 

 balsam. 



For Reich's tt granules he stains frozen sections of formalin 

 material in 1 per cent, toluidin blue for one hour, washes 

 thoroughly in distilled water and differentiates, less completely 

 than for Nissl granules, with alcohol. 



METHODS FOR PROTOPLASMIC NEUROGLIA 

 OLIGODENDROGLIA AND MICROGLIA 



1093. Ramon y Cajal's Gold Chloride and Sublimate Method 



{I'rah. Lab. Invest. Biol., Madrid, xi, 1913, pp. 219 and 255 ; xiv, 

 1916, p. 155). At first Cajal used to harden pieces of quite fresh 

 tissues in 14 per cent, formalin, but in his successive papers he 

 recommended fixing from two to ten davs in — 



Formol . . . . . .15 c.c. 



Ammonium bromide .... 1-5-2 crm. 



Distilled water . . . . .85 c.c. 



Relatively thick sections (20 to 25 /x) arc made by the freezing 



VADK-llKCUM. 18 



