122 BOTANICAL MICROTECHNIQUE. 



d. Brncinc, C 23 H 26 N,O 4 + 4H 2 O. 



213. For the recognition of brucine, which accompanies: 

 strychnine in the seeds of Strychnos nux-vomica, Lindt (II,. 

 239) used a mixture of five drops of selenic acid, of specific 

 gravity 1.4, and one or two drops of nitric acid, of specific 

 gravity 1.2. He allowed this to run under the cover-glass 

 to thin sections whose fat had been extracted by petroleum- 

 ether. The stratified cell-walls then quickly became bright- 

 red, but gradually changed to orange and yellow, while the 

 cell-contents remained colorless. Lindt concluded from this 

 that only the walls contain brucine (cf. also 219). 



e. Colchicine, G, 2 H 25 NO 6 . 



214. Colchicine occurs, according to O. Herrmann (I, i8) r 

 in the corm of Colchicum autumnale, in the contents of two- 

 or three rows of cells which immediately surround the 

 vascular bundle and are distinguished from the neighboring 

 parenchyma-cells by being free of starch. For the recogni- 

 tion of colchicine this author used ammonia, which turns it 

 a deep yellow. 



Errera, Maistriau and Clautriau (I) have lately character- 

 ized it as giving a yellow color with sulpJiuric acid diluted 

 with two or three volumes of water, a brown-violet with sul- 

 phuric and nitric acids, a brown with iodine, and a yellowish 

 precipitate with potassic-merciiric iodide and hydrochloric 

 acid. 



f. Corydalin, C 18 H 19 NO. 



215. According to Zopf (VI, 113), corydalin shows the 

 following reactions : It is precipitated from aqueous solu- 

 tions of its salts by caustic alkalies and alkaline carbonates, 

 but is redissolved in an excess of the former. A brown 

 precipitate is produced in solutions of its salts by solutions 

 of iodine or of iodine and potassium iodide, a yellow one by 

 potassium chromate, a white one by mercuric chloride, a 

 yellow one by gold and platinum chlorides and by sodium 

 metatungstate, a yellowish-white one by potassic-mcr curie 



