8o2 BOTANY AND PHARMACOGNOSY. 



to decomposition, may, however, be kept for months or even )ears 

 by preparing them with care and keeping them in a special kind 

 of bottle (Fig. 321). An ordinary bottle may be used, and is 

 fitted with a rubber stopper perforated so as to allow the intro- 

 duction of two glass tubes. These tubes are bent twice at right 

 angles and the free ends directed downwards. One of the tubes 

 is connected with an atomizer bulb and serves for forcing out the 

 liquid. A small plug of absorbent cotton is placed in the tube 

 at the point C, so as to filter the air. This may be improved by 

 blowing a bulb in the tube for holding the cotton. The bottle 

 should be sterilized before placing the solution in it, and the solu- 

 tion should be made by adding the dye to sterile water contained 

 in the bottle. The solution may be afterwards further sterilized 

 by means of steam if this should be found necessary, as in this 

 way only a perfectly sterile solution could be produced. 



The non-aniline stains give, as a rule, more reliable and con- 

 stant results in the study of cell walls, as in the roots, stems and 

 other parts of the plant, than the aniline stains. They include 

 the following : 



Beale's Carmine Solution, which is made as follows: Mix 

 0.6 Gm. carmine with 3.75 Gm. ammonia water (10 per cent.) ; 

 heat on a water-bath for several minutes ; then add 60 Gm. of 

 glycerin, 60 Gm. of water and 15 Gm. of alcohol, and filter. 



Grenacher's Borax-Carmine Solution. — Disolve 2 to 3 

 Gm. of carmine and 4 Gm. of borax in 93 c.c. of water and then 

 add 100 c.c. of alcohol (70 per cent.) ; shake and filter. When 

 this stain is employed the sections are freed from an excess by 

 the use of alcoholic solutions of borax or oxalic acid. 



Hover's Picro-Carmine Solution is made by dissolving 

 carmine in a concentrated solution of neutral ammonium picrate. 

 A solution of carmine and picric acid is known as Picro-Carmine 

 Solution. 



Chlor-zinc-iodide Solution, or Schulze's Cellulose Reagent, 

 consists of anhydrous zinc chloride, 25 Gm. ; potassium iodide, 8 

 Gm., and water, 8.5 Gm., to which as much iodine is added as 

 the solution will dissolve. 



Bohmer's Hematoxylin Solution is prepared by mixing 

 the two following solutions and filtering after allowing the mix- 



