Naturalisation in Extra-Tropical Countries. 415 



Polygala Senega, Linn6. 



The Senega Snake-Root. Eastern North- America. A perennial 

 herb. Senega-root is of medicinal value, and about 100,000 Ibs. of 

 it are required annually. 



Polygaster Sampadarius, Fries. 



South-Eastern Asia. One of the most palatable of all truffles. 



PolygfOimm CUSpidatum, Siebold and Zuccarini. 



Japan. A large perennial herb, easily mistaken for P. Sacha- 

 linense, but not of the same fodder-value. It serves for binding loose 

 sand and solidifying embankments [K. Weigelt in Erfurt Gaertner 

 Zeitung, 1894, p. 187]. It differs from the following species in 

 having shorter leaves, which are neither heart-shaped at the base nor 

 bluish-green beneath [Engelhardt], 



Polygonum Sachalinense, Fr. Schmidt. 



Islands of Sachalin and Yesso. Giant Knot- weed ; in Bengal known 

 as " Machute," according to the Indian Agriculturist. This spacious 

 perennial herb has latterly been recommended as a fodder-plant, 

 particularly by M. Doumet Adanson and Professor Duchartre. In 

 the first year one or two cuts are obtained, in the second year three or 

 four cuts. It may reach a height of 10 feet in three weeks [Louis 

 Haase]. Numerous annual shoots arise from one root-stock. The 

 leaves attain 1 foot in length and 9 inches in width. The edible 

 root-stock gets finally as thick as a man's arm, sustaining the plant 

 in its green freshness during the driest season. It will live in a 

 temperature from 22 F. to + 104 F. Horses are particularly 

 fond of the foliage, which also serves for packing and displaying 

 fruit. The plant is eligible for scenic culture, and is further a good 

 bee-plant, flowering at the end of the summer. Commissioner 

 Marsden says that the points in its favour are : " Once planted, stands 

 for ever. Water will not drown it ; fire will not destroy it. Endures 

 severest drought with impunity. Roots penetrate deep into the soil. 

 Requires no ploughing before planting. Needs no cultivation. 

 Grows where no other forage plant will exist. Grows in poorest soils. 

 Is more nutritious than clover or alfalfa. Affords shade to cattle in 

 hot climates. Stem and leaves, green or dry, greatly relished by 

 cattle." Birds feed on the seeds of any Polygonums. 



Polygonum tinctorium, Aiton. 



China and Japan. An annual herb, deserving attention and 

 local trials, as yielding a kind of indigo ; one of the most important 

 dye-plants of Japan. It can be cultivated in cold climes, being 

 hardy still at Christiania. Likes marshy land [Vilmorin]. Its 

 growth would be vigorous. Various Polygonums contain tannin, 

 P. amphibium (Linne) as much as 11 \ per cent. [Masters.] 



