DR wniiillTS HERBARIUM 287 



be shewn. They require longer or shorter immersion, ac- 

 cording to the age of the plant : and the hemp or flax dif- 

 fers in quality and strength, according to its nature.; and, 

 in point of colour, as it may happen to be soaked in run- 

 ning water, clear ponds, or muddy holes. These simple hints 

 may induce some fit person to make experiments with the 

 plants of this class in Britain, whose strength depends so 

 much on her naval force, and whose treasures are yearly 

 expended in purchasing hemp and flax from foreign nations, 

 when she might at less expence be supplied at home, or in 

 her extensive colonies. 



This species requires that the bark be stripped, and soaked 

 for four days. The flax or hemp is very strong. 



107"^ Urena Amkricana, L. var. — Bur-Mallows with deep 

 indented Leaves. 



This grows in moist places, by the highway ; having many 

 green stalks springing from one root, long, smooth, and slen- 

 der. The leaves are very pretty. The blossoms appear in 

 June, and the bur, which is ripe in August, is prickly, 

 and opens in five parts, when ripe, to discharge as many heart- 

 shaped seeds, of a chocolate colour. 



The stalks require about eight days' soaking, when they 

 yield a hemp of tolerable strength. 



108. Pavonia spinifex, L.var. — Jamaica Mallow, or Spur-Bur. 



This grows wild in shady places, and in fences, having 

 many long, smooth, slender stalks, springing from one root 

 These have a few furrowed leaves, and pretty large blossoms, 

 whose petals are lapped over, contrary to the motion of the 

 sun. 



The fruit is a bur, which sends off from each side long 

 prickles, and resembles a spur— hence the name. 



