694 HUBER. [Vol. XI. 



flowing water for about thirty minutes, and placed into ninety- 

 five per cent alcohol for three or four days. 



(To keep the nerve fibres straight during the process of 

 hardening the following device was made use of : One end of 

 each of two small glass rods, the one about eight, the other 

 about three inches long, was pushed through a cork of a size 

 to fit a six-inch test tube ; the other ends of the two rods were 

 bent in the form of a hook. After removing a nerve segment 

 from a dog its central end was tied to the short hook, its dis- 

 tal end to the long one, and the long rod was moved up or 

 down in the cork until the nerve attained the proper degree of 

 extension. The hardening was then carried on in a test tube.) 



After remaining in ninety-five per cent alcohol the required 

 time, each nerve was divided into pieces varying in length from 

 one-half to one inch. Two consecutive segments, one of which 

 was used for longitudinal, the other for transverse sections, were 

 placed in properly labeled test tubes, in which they were carried 

 through absolute alcohol, toluol, soft and hard paraffin, and 

 were then imbedded in a mixture composed of four parts of 

 hard paraffln and one of spermaceti. 



Sections varying in thickness from five to ten mikrons were 

 cut and fixed to a cover glass by a method described by the 

 author in a former paper. The method consists in floating the 

 paraffin sections on distilled water, then carefully warming the 

 water until they flatten out, which they usually do very readily, 

 A thin layer of " albumin fixative " is now spread on a cover 

 glass ; this is then inserted under the sections floating on the 

 water, one or more of which are drawn up on the cover glass, a 

 small sable-hair brush being used for this purpose. When this 

 has been done, the cover slip with the sections on it is drawn 

 out of the water and set aside, best in a warm oven at forty 

 degrees C. for several hours. Nearly all the albumin fixative is 

 washed away, so it does not interfere with the staining, yet 

 enough seems to remain on the cover to cause the section to 

 adhere more firmly than when water is used, as recommended 

 by Gaskell, or when fifty to seventy per cent alcohol is em- 

 ployed, as recommended by Gaule. 



Cutting in paraflin admits of thinner sections than when 



