TASTE-BUDS. 283 



and across the direction of the ridges. The sections 

 are stained and mounted as usual. 



The piece that was placed in osmic acid may be 

 used at the end of forty-eight hours. In the first 

 place two or three sections are to be obtained like 

 those made from the other piece, without however 

 embedding the tissue, but simply holding it in the 

 fingers or in a piece of split cork. One such section 

 is to be placed in a drop of water on a slide, and an 

 attempt made with needles, under the dissecting 

 microscope, to separate some of the taste-buds from 

 the surrounding epithelium. For this purpose the 

 needles must be very fine, sharp, and clean, and the 

 lens used as high as is consistent with convenience 

 of manipulation. When one or more taste-buds have 

 been thus separated, the rest of the section is re- 

 moved, and the isolated buds are broken up as com- 

 pletely as possible into their constituent cells. The 

 specimen may then be covered, and a drop of glyce- 

 rine allowed to diffuse in under the edge of the 

 cover; after which an examination of the [(repara- 

 tion may be made, at first with the ordinary high 

 power, and afterwards with an immersion objective. 



