CRUDE DRUGS. 559 



with alkalies, purple with potassium alum, and olive-green chang- 

 ing to greenish-brown with ferric chloride. 



V. FRUITS. 



The fruits of a large number of plants are used in medicine ; 

 these vary greatly, not only in their medicinal properties, but also 

 in their botanical origin. The active principles of fruits vary 

 according to their stage of development, so that fruits which 

 contain relatively large amounts of poisonous principles when 

 green or immature, may be quite free therefrom and even edible 

 when they are ripe. It is for this reason that by far the larger 

 number of medicinal fruits are collected in the fully developed 

 but unripe condition. (See Classification of Fruits, p. 151.) 



KEY FOR THE STUDY OF FRUITS. 



I. Entire Fruits. 



I. Not more than 10 mm. long (exclusive of the stalk). 



A. Cremocarps. 



a. Hairy. 



Slender pedicel, 4 to 10 mm. long Anisum 



h. Nearly smooth. 



u. Mericarps more or less miited. 



Nearly globular Coriandrum 



Oblong, pedicel, 3 to 10 mm. long Fosniculum 



^ Mericarps usually separate. 



Dark brown, odor and taste aromatic Carum 



Grayish-green, odor peculiar Conium 



B. Dry drupes. 



a. Hairy. 



Pericarp reddish Rhus Glabra 



b. Not hairy. 



a Coarsely reticulate. 



Slender pedicels, S to 7 mm. long Cubeba 



Stalk wanting Piper 



j3 Not reticulate. 



Inferior drupe Pimenta 



C. Caryopsis or Grain Barley 



