NAT. ORDER. 



Rotaccce. 



HYPERICUM PERFORATUM. ST. JOHN'S WORT. 



Class XVIII. PoLYADELPHiA. Order V. Polyandria. 



Gen. Char. Calyx five-parted. Petals five. Filaments many, con 

 nected at the base, in five bundles. 



Spe. Char. Stem ancipital. Leaves blunt, with pellucid dots. 



This species of the Hypericum is found growing abundantly both 

 in Europe and in this country, often covering whole fields, and proving 

 extremely troublesome to farmers. It usually grows in uncultivated 

 fields, from one to two feet in height, producing its tlowers in July and 

 August. The root is perennial, ligneous, divided and subdivided into 

 numerous small branches, and covered with a straw-colored bark ; the 

 stalks are round, smooth, of a light color, and towards the top send 

 off many opposite floriferous branches ; the leaves are without foot- 

 stalks, and placed in pairs ; they are entire, oval, and beset with a 

 great number of minute, transparent vesicles, which have the appear- 

 ance of small perforations through the disk, and hence the specific 

 name Perforatum ; the Jloicers are numerous, pentapetalous, terminal, 

 of a deep yellow color, and grow in a corymbus, or in clusters, upon 

 short peduncles ; each petal is of an irregular oval shape, and on the 

 under side near the apex is marked with many blackish dots ; the calyx 

 consists of five persistent acute leaves ; the stamens are numerous, 

 and generally unite at their base into three portions or bundles ; the 

 anthers are yellow, and marked with a small black gland, by wliich 

 this species of the Hypericum is at once distinguished ; tlie styles are 



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