No. 3-] PERIPHERAL NERVES. 695 



celloidin is used, as Stroebe recommends, and the technic of 

 staining is simpler. The cover glass can be handled much 

 more easily than thin celloidin sections. Then, too, one can 

 often fix ten to fifteen sections to one cover, so there is a great 

 saving of time. The paraffin is removed in the usual way, and 

 then the cover with the sections on it is carried through " the 

 alcohols " into distilled water. 



The technic of Stroebe's anilin blue-safranin method is as 

 follows : — 



(i) Sections are stained from one to five hours in a saturated 

 aqueous solution of anilin blue (Griibler's wasserlosliches Anilin- 

 blau). 



(2) They are then rinsed in distilled water, 



-(3) Decolorized in an "alkali alcohol wash," which is pre- 

 pared by dissolving i grm. of caustic potash in 100 c.c. of 

 absolute alcohol, and filtering. Just before using thirty to 

 forty drops of this solution are mixed with 30 c.c. of absolute 

 alcohol. On placing the sections into this wash they lose their 

 blue color, and assume a reddish-brown tinge; at the same time 

 reddish-brown waves are given off from the preparation. The 

 bleaching is continued until the reddish-brown waves cease to 

 form, which usually takes about one to two minutes. If many 

 sections are to be bleached it will be found necessary to renew 

 the alkali wash. 



(4) The sections are now transferred to distilled water, in 

 which the blue color again returns, of a much lighter hue, how- 

 ever. The sections remain in the water about ten minutes. 



(5) Counter-stain in a saturated aqueous solution of safranin 

 for about one-half hour. 



(6) Rinse in distilled water. 



(7) Wash and dehydrate quickly in ninety-five per cent, then 

 in absolute alcohol. 



(8) Clear in oil of bergamot, and place the sections into 

 xylol, from which they are mounted in Canada balsam. The 

 xylol leaves a clean surface on the cover after evaporating, and 

 is for this reason to be used after oil of bergamot. 



The axis cylinder will be stained deeply blue, the myelin red- 

 dish-yellow, or of an orange tinge, and the nerve nuclei, and all 



