1 86 PLANT ORGANS OR PARTS OF PLANTS. 



oxalate crystals; belladonna in the form of fine powder 

 (sand crystals) ; stramonium, sand crystals and agglom- 

 erations; hyoscyamus, large single crystals. 



In digitalis, as stated, all forms of calcium oxalate 

 crystals are entirely absent. 



Chemistry. — The chemistry of digitalis is complex and 

 as yet incompletely studied. There are in the market 

 a large number of commercial products. The French and 

 German digitalins, however, are supposed to represent the 

 drug. Neither do so completely. Schmiedeberg (1874- 

 75) has isolated four principles, all free from nitrogen — 

 digitonin, digitalein, digitalin, and digi toxin; further, 

 there are present two acids, digitalic and antirrhinic, 

 a stearopten, digitalosium, inosite, and ash, 10.5 per cent. 

 Reduction compounds of the glycosides are common. 



Digitonin, Cg^H^jOi^, is an amorphous glycoside, 

 similar to saponin, readily soluble in water, slightly so in 

 alcohol, insoluble in ether, chloroform, and benzin. 

 Boiled with dilute acids, it splits up into glucose and two 

 amorphous principles. 



Digitalein, the existence of which has been questioned 

 by Kiliani, is described as an amorphous white powder, 

 readily soluble in water, alcohol, and ether. 



Digitalin, C5Hg02, is amorphous or distinctly crystal- 

 line, difficultly soluble in water and ether, easily soluble 

 in alcohol. Heated with acids, it splits up into glucose 

 and digitalin-resin. It is the principal constituent of the 

 amorphous French digitalin. 



Digitoxin, C21H32O2, crystallizes in needles. It is 

 soluble in chloroform and hot alcohol and ether, not at all 

 in water or benzin. Boiled in alcoholic solution with 

 dilute acids, it yields amorphous toxiresin. Digitoxin, 

 which is the most active of the constituents of digitalis, 

 forms the greater portion of crystalline French digitalin. 



Kiliani has more recently shown that there are differ- 

 ences in the contents of these bodies in seed and in the 



