188 SEEDS 



which, when quite fresh, are pale in colour, but darken as they dry, 

 becoming at the same time covered with a saccharine exudation, as 

 much as 5 per cent, of glucose having been found on them. These 

 were introduced into medicine about 1820 to replace the corm, which 

 was considered uncertain in action. 



Description. Colchicum seeds are small, very hard, and of a dull 

 dark reddish brown colour. They are about 2*5 mm. in diameter 

 and nearly spherical, the remains of a thick funiculus rendering them 

 somewhat pointed. Under a lens the surface is seen to be rough 

 from the presence of minute pits. They are extremely hard and 

 tough, and are difficult to cut until they have been soaked in water ; 

 the section exhibits a yellowish, oily endosperm, in which, near the 

 margin and removed from the hilum, the minute embryo is embedded. 

 They are odourless, but have an unpleasantly bitter taste. 



The student should observe 



(a) The rough surface and hard nature of the seed, 

 (6) The remains of the thick funiculus ; 



and should compare them with 



(i) Black mustard seeds, which are smaller, 



(ii) Henbane seeds, which are reniform in outline. 



Constituents. All parts of the plant contain the alkaloid, colchicine, 

 which possesses weak basic properties. The seeds contain from 0-02 

 to 0-8 per cent., but a good sample of the drug should yield not less 

 than 0-5 per cent. The seeds also contain a resin, colchicoresin, and 

 about 6 per cent, of fixed oil. They yield about 3 per cent, of ash. 



Colchicine, C 22 H 25 N0 6 , crystallises in pale yellow needles melting at 155 to 

 157 and yields a crystalline compound, C 2 2H25N0 6 .2CHC1 3 , with chloroform. 

 The alkaloid is very soluble in cold water, alcohol, and chloroform, but only 

 slightly in ether. Chloroform removes it from an acid as well as from an alkaline 

 aqueous solution ; boiled with dilute mineral acids it yields colchiceine and 

 methyl alcohol. Colchicine has also been found in the root of Gloriosa superba, 

 Linne. 



Assay. The seeds may be assayed by the process devised by Farr and Wright. 1 



5. Colchicum is chiefly used to relieve the pain and inflammation 

 and shorten the duration of acute gout and certain gouty affections. 

 Its action depends upon the alkaloid colchicine. Colchicine has a 

 marked action upon plain muscle, especially that of the intestine, 

 producing diarrhoea and vomiting. In large doses it produces death 

 from failure of the respiration. 



Adulteration. Colchicum seeds are said to be liable to adulteration 

 by the fraudulent addition of glucose. 



1 Yearbook of Pharmacy, 1911, p. 23. 



