MICROCHEMIS TRY. 123 



chloride, a white one by potassium sulplio-cyanide. The 

 solution in spirit is precipitated by strong alcohol. 



For its microchemical recognition Zopf used especially 

 ammonia, which produces a dark gray, granular precipitate 

 in the cells containing corydalin, and iodine with iodide of 

 potassium, which causes a deep red-brown precipitate. Picric 

 acid also causes, according to Zopf, a readily recognizable 

 precipitate in corydalin-bearing cells. 



g. Cytisine, C 20 H 27 N 3 O. 



216. Cytisine occurs, according to Rosoll (I, 24), in all the 

 organs of Cytisus Laburnum, but most abundantly in the 

 contents of the cells of the ripe seed. This author uses the 

 following reactions for its recognition : 



Iodine and iodide of potassium give, even when very dilute, 

 a brownish color and then a dark red-brown precipitate, 

 soluble in sodium hyposulphite. 



Picric acid, added to thin sections, produces in a short 

 time scale-like crystal-groups of a reddish-yellow color. 



Concentrated sulphuric acid dissolves cytisine with a bright 

 reddish-yellow color ; if very small bits of solid potassium 

 bichromate be added to this solution, it becomes first yellow, 

 then brown, and finally green. 



Phospho-molybdic acid produces immediately a yellow tur- 

 bidity in the sections. 



//. Opium Alkaloids. 



217. According to the investigations of Clautnau (I), 

 several of the so-called opium alkaloids occur in the Tatex 

 of the living plant in Papaver somniferum. 



i. Morphine, Ci 7 Hi 9 NO 3 . 



The presence of morphine is recognized by this author 

 by the fact that the latex gives precipitates with iodine and 

 potassium iodide, potassium-bismuth iodide, potassium-calcium 

 iodide, potassic-mercuric iodide, and phospho-molybdic acid - 



