POLYGONUM SAGITTATUM. 



ARROW-LEAVED TEAR-THUMB. 



Octandria Trig-ynia, Linn. Polygonex, Juss. 



GENERIC CHARACTER. 



Cal'ix 5-parted, petaloid, persistent. Seed 1, superior, 3-sided, covered by the conni- 

 vent calix. (The number of the styles and stamina uncertain.) 



SPECIFIC CHARACTER. 



Flowers in heads, octandrous, with the style 3-cleft; stem retrorsely aculeate; leaves 

 sagittate. Mich. 



A weak decumbent annual plant, supporting itself by clinging to 

 other plants. Stem green, four-sided, beset backward with prickles, 

 not so rigid as those of the preceding species, but injuring the fingers 

 in the same manner if handled. Leaves shaped like the head of an 

 arrow, with the margins curved in an arch from the apex to the base 

 of the auricles. Flowers white, in clusters. Petals white, tinged with 



vol. in. 23 



