CELL-CONTENTS AND FORMS OF CELLS. 



1^1 



ing the amount of water they dissolve and are diffused among the 

 other constituents. If fresh sections are mounted directly in 

 alcohol, or if to the original aqueous mount strong alcohol is 

 added, the inulin separates in the form of rod-like or needle-like 

 crystals, which strongly polarize light. If the plant material is 

 preserved for some days in 70 per cent, alcohol, the inulin separates 

 in the form of sphere-crystals which adhere to the walls of the cell. 

 This aggregate consists of concentric layers of radially arranged, 

 needle-shaped crystals, the structure of which is more apparent 

 upon the addition of either nitric acid or a solution of hydrated 

 chloral. The crystal mass is insoluble in glycerin and sparingly 

 soluble in cold water. It is soluble in warm water, warm solu- 

 tions of glycerin and water, acetic acid, mineral acids, chlor- 

 zinc-iodide, and ammoniacal solution of cupric oxide. With solu- 

 tions of the alkalies it dissolves with a lemon yellow color, and 

 with acetic acid the crystals dissolve, forming a greenish colored 

 solution which soon fades. 



Tunmann {Ber. d. d. pharm. Ges., 1910, p. 577) has sug- 

 gested the use of a solution of pyrogallol as a distinctive re- 

 agent for the microscopic study of inulin. The solution con- 

 sists of o.ioo Gm. Pyrogallol, alcohol 5 c.c, and 5 c.c. of hydro- 

 chloric acid. Upon carefully heating sections treated with this 

 reagent the cells containing inulin are colored a violet red. A simi- 

 lar solution made with resorcin in place of pyrogallol colors inulin 

 a cinnabar red. 



In taraxacum, inula, pyrethrum, and other drugs inulin occurs 

 in the form of an amorphous mass having a more or less angular 

 outline. The masses are highly refracting and probably consist 

 of aggregates of small crystals similar in appearance to those of 

 mannit found in commercial manna. 



Hesperidin. — Although not a carbohydrate, hesperidin is of 

 wide occurrence and separates in the form of sphero-crystals re- 

 sembling inulin. It is a glucoside (CooH.,50io), and it would 

 appear, from the studies of Tunmann (Sclizveic. JVocJi. f. Chcm. u. 

 Pharm., igog, p. 794), that, like inulin, there are several forms 

 of it. Hesperidin, like inulin, occurs in living cells in the form 

 of a more or less viscous fluid. Upon the addition of water, 

 alcohol, glycerin, or solutions of hydrated chloral it separates in 



