NON-POISONOUS DRUGS 



167 



expressed oil of almond, olive-oil, and the oil of cacao seed 

 known as cacao butter, already studied for their food value 

 (in sections 33 and 39) ; and to these may now be added castor- 

 oil and the oily drug lycopodium. Castor-oil, obtained from 

 the seeds of the castor-oil plant (Fig. 165), is believed not 

 to be taken up by the digestive tract as a food, but to owe its 



Fig. 1.59. — English Elm (Ulrmis campestris, Elm Family, Ulmacew). 1, 

 flowering twig. 2, leafy shoot. 3, flower, entire. 4, same, cut ver- 

 tically. 5, fruit. (Wossidlo.) — Tree attaining 30 m.; leaves becoming 

 smooth; flowers greenish or brownish; fruit yellowish. Native home, 

 Eurasia and Northern Africa. 



great medicinal value to its lubricant and mildly irritant 

 properties. The sulphur-yellow powder known as lycopo- 

 dium, obtained from the club moss (Fig. 166), consists of 

 minute bodies called spores by means of which the plant per- 

 petuates its kind. Each spore contains nearly 50% of a 

 fixed oil, and the surface is remarkably repellent of water. 

 A teaspoonful of the spores thrown into a bowl of water Avill 



