684 BOTANY AND PHARMACOGNOSY. 



cultivated, are also used in medicine. The leaves are 4-ranked, 

 of two kinds, those of the lateral pairs being more or less elon- 

 gated, clasping, and triangular in section, those of the other pair 

 being flattened, appressed and with a prominent oleo-resinous 

 gland near the middle on the dorsal or outer surface, the arrange- 

 ment of the leaves being such as to give the branches a flattish 

 appearance. The fruits are small cones with six to ten carpels, 

 each bearing a narrow-winged seed. Thuja contains i per cent, of 

 a volatile oil with an odor resembling tansy and containing d-pi- 

 nene, 1-fenchone, d-thujone. and an inactive oxime ; two resins; a 

 glucoside thujin, which resembles quercitrin ; a bitter glucoside 

 pinicrin, and pinitannic acid (which two latter principles are also 

 found in Pin us sylvestris) . 



DRUGS DERIVED FROM THALLOPHYTES AND 

 ARCHEGONIATES. 



Not very many of the lower plants furnish important drugs, 

 there being probably not more than five or six drugs from this 

 source that are official in the different pharmacopoeias. For pur- 

 poses of identification they may be grouped as follows : 



Rhizome^ Aspidium 



Entire, yellowish-white, cartilaginous thallus. . . .Chondrus 



Entire, grayish-brown, papery thallus Cetraria 



Purplish-black cylindrical grains Ergota 



Light yellow powder Lycopodium 



ASPIDIUM. MALE FERN. The rhizome and stipes 

 of Aspidium (Dryoptcris or Nephrodiuui) Filix mas and Aspid- 

 ium marginale (Fam. Polypodiacese), perennials, of which Aspid- 

 ium Filix mas (Fig. 277) is more widely distributed, being 

 indigenous to Europe, Asia, North America, west of the Rocky 

 Mountains, and in the Andes of South America; while A. mar- 

 ginale is found in the Eastern and Central United States and 

 extends north to Prince Edward's Island (p. 61). The rhizome 

 is collected in early autumn, the leaves cut off, leaving the lower 

 portions or stipes attached to the rhizomes ; the dead portions of 



