7<5o A TEXT-BOOK OF BOTANY. 



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. Dissolve 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. Carmine solutions give to cellulose, the nucleus and 

 proteins a red color. 



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. This reagent gives a violet color with 

 cell-walls containing cellulose. Of the cell-contents, starch is the 

 only one which is affected by it, being colored blue. 



BOHMER'S H.EMATOXYLIN SOLUTION is prepared by mixing 

 the two following solutions and filtering after allowing the mix- 

 ture to stand for several days: (a) one part of a 3.5 per cent, 

 alcoholic (95 per cent.) solution of hsematoxylin and (b) three 

 parts of a 0.4 per cent, aqueous solution of potassium alum. 



DELAFIELD'S H^MATOXYLIN SOLUTION, which is also incor- 

 rectly called " Grenacher's Haematoxylin Solution," is made by 

 mixing the following solutions: (a) Haematoxylin 4 Gm., alcohol 

 25 c.c., and (b) 400 c.c. of a saturated aqueous solution oi ammo- 

 nia alum ; this solution is exposed to the light for three or four 

 days, filtered, and then 100 c.c. each of glycerin and methyl alco- 

 hol are added, the solution allowed to stand for several days and 

 finally filtered. An excess of the stain is removed from the sec- 

 tions by subsequent washing either with a 2 per cent, alum solution 



