150 Journal of Comparative Neurology. 



in the same ratio there are no empty spaces left about the cell 

 body. 



In the specimens fixed with alcohol-formalin one is struck 

 at first sight by the variation in the staining, these sections tak- 

 ing up methylene blue as well as thionine blue quite strongly, 

 more so than the preceding. In the ganglion cells the body is 

 separated from the surrounding structures slightly ; whether 

 this is due to its contraction or the contraction of the surround- 

 ing tissues away from it, could not be definitely determined. 

 The granules are slightly indistinct, poorer than with specimens 

 preserved with absolute alcohol. With formalin 20^ the stain- 

 ing was even more intense than with the preceding and the con- 

 traction of or away from the ganglion cell body was marked. 

 Yet the chromophilic granules came out distinctly. Fixation 

 with Hermann's fluid gave the worst results. The contraction 

 was uniform throughout but the granular structure was irreg- 

 ular, lumpy or broken up'into fine granular masses. Flemming's 

 fluid gave better results, the chromophilic granules being 

 often quite sharp and well preserved ; contraction was marked, 

 as with the Hermann's. 



Thus alcohol 95 ^ and sat. alcoholic sol. of corrosive sub- 

 limate gave the sharpest pictures. 



As to the use of thionine blue, instead of methylene blue, 

 the comparisons made were in favor of the methylene blue. 



With reference to the mounting media, I cannot feel that 

 there is much preference to be shown. Nissl highly recom- 

 mended benzine colophonium but in the experiments made I 

 could not say that I could detect any differences in the media 

 used, and on submission of the slides to Dr. Strong he could 

 not tell that there was any difference. Perhaps after a lapse of 

 some time there may be differences. Benzine colophonium dries 

 very rapidly and hence may have an advantage in the long run, 

 but after a lapse now of twelve months, the specimens still look 

 alike to my eyes. If I were to express any preference it would 

 be for xylol damar, not on account of its being better but the 

 clearness of the resin is pleasant. Many of my benz. coloph. 

 specimens were of no value at the end of six months. Chlor- 



