CRUDE DRUGS. 691 



glucose. Evernia prnnastri contains a carbohydrate evernin, which 

 resembles lichenin but is dextrogyrate. The following lichens 

 do not contain lichenin. but yield carbohydrates which on hydro- 

 lysis give little or no glucose: Cladonia rangiferina contains 30 

 per cent, of mannose ; Stercocaulon pascalc and Pcltigeria 

 aphthosa yield on hydrolysis dextromannose and dextrogalactose. 



ERGOTA. ERGOT OF RYE. The sclerotium of Clavi- 

 ceps purpurea (Fam. Hypocreacese), a fungus having two dis- 

 tinct periods in its life history an active and a resting stage 

 (Fig. 19). During the latter it forms a compact mycelium, or 

 sclerotium, which replaces the flowers and grains of rye. Ergot 

 is picked by hand from the ears of rye, or it is separated after the 

 thrashing of the rye ; it is carefully dried, and preserved against 

 the attacks of insects by the use of small quantities of chloro- 

 form. It deteriorates with age, particularly when powdered, and 

 is not considered so valuable after one year. Various methods 

 have been proposed for preparing the drug so as to preserve its 

 medicinal properties for a longer period of time (p. 422). Rus- 

 sia, Spain and Germany furnish the chief part of the commercial 

 supply, the Russian drug being considered the most active (p. 27). 



Spanish ergot usually consists of large grains, having a fine 

 appearance, but is not so active as that from the other countries 

 mentioned, and contains considerable starch. 



Description. Sub-cylindrical, tapering toward but obtuse at 

 both ends, somewhat curved, 2 to 4 cm. long and about 3 mm. 

 thick ; externally purplish-black, longitudinally furrowed, occa- 

 sionally transversely fissured, one end with the whitish remains 

 of mycelial threads, fracture short ; internally whitish or pinkish- 

 white, sections somewhat triangular or two-lobed ; odor peculiar, 

 heavy, increased by trituration with potassium or sodium hydrate 

 solution ; taste oily and disagreeable. 



Constituents. The constituents of ergot have been the sub- 

 ject of considerable investigation, and the results have been more 

 or less contradictory. Of the large number of substances which 

 it contains the following may be mentioned : 



The most important physiologically active substances are 

 cornutine and sphacelinic acid. The crystallizable alkaloid cornu- 

 TiNE of Keller is insoluble in water and the dilute alcoholic solu- 



