1399] MICROSCOPICAL JOURNAL. 47 



glycerine, or in fact any media where small quantities are 

 required at a time, is one invented by Dr. Needham, a 

 gentleman of great experience in microscopical matters. 

 It consists of a specially made bottle with a glass dipping 

 rod of its own. This rod is provided with a small flange, 

 fitting into a shoulder, ground out in the neck of the 

 bottle. When not in use, the dipper or rod is placed in 

 the bottle, and taken up as required. The surplus media, 

 whether it be balsam or any other gets into the shoulder 

 in the neck, preventing all evaporation, and at the same 

 time it never holds tight enough to fix the rod. It is 

 always ready for use, and going back into its place when 

 not required, is the cleanest apparatus of the kind yet 

 made. Balsam may be kept for any length of time with- 

 out evaporation. One is saved the trouble of getting a 

 cork out, and consequently no pieces can be left behind. 

 It is superior to the bottles that are made with ground 

 glass cap. In them the cap is always getting fastened on, 

 then resource has to be had to heat, and the bottle is often 

 broken. 



Mounting in Glycerine. — Many delicate vegetable 

 and other tissues are best mounted either in a cell, or in 

 glycerine in the form of a jelly. Take as an example, 

 the spinnaret of the Garden Spider to be mounted in the 

 former without pressure in a cell. This is a most beau- 

 tiful object with the spot lens and 2 in. objective, well re- 

 paying the trouble in mounting. Take a 3 X 1 in. slip, 

 with cell of suitable depth fixed on it. A transparent bot- 

 tom to the cell will be required. A cell of about 5-8 in. 

 or not less than 1-2 in. is a good size for this object. Run 

 a ring of cement round the top as with other cell mounts. 

 With a clean brush dipped in distilled water, damp the 

 ' cell in the inner edge all round, also on the bottom. This 

 will get rid of any air that may cling to the cell. Get rid 

 of any excess of water with a small piece of blotting 

 paper. Carefully put in the glycerine until the cell is 



