ROSACEA. 



279 



stimulating. Dr. A. T. Thomson speaks well of it in the colliquative diarrhcea 

 of phthisis. It is also beneficial in aphthous sores of mouth and gums, 

 and has been used as an external application to ill-conditioned ulcers. 

 At one period its reputation was very great in the plague and other malignant 

 diseases, and it was recommended by Vesalius as equal to guaiacum in the 

 treatment of syphilis. It is seldom or never employed in this country, where 

 there is such a number of native remedies of similar and even superior powers. 

 The dose in substance is from half a drachm to a drachm. It is employed in 

 some parts of Scotland for the purpose of tanning leather, and in Lapland as 

 a dye. 



Geum. — Linn. 



Calyx sub-campanulate, deeply five-cleft. Petals five, obtuse, or emarginate. Stamens 

 numerous; filaments somewhat persistent. Achenia numerous, dry, aggregated in a 

 conical or cylindrical head, caudate with the persistent styles. 



An extensive genus of perennial herbs, with variously pinnately divided 

 leaves, and white, yellow, or purplish flowers. It has been separated into a 

 number of other genera by different botanists, but most of these are not enti- 

 tled to a higher rank than that of sub-genera or sections. The species which 

 are most numerous in North America, are peculiar to cold and temperate cli- 

 mates, and are all more or less possessed of astringent qualities, and may be 

 substituted one for the other without inconvenience. The G. urbanum is 

 officinal in some of the foreign pharmacopoeias, and the G. rivaZe in that of 

 the United States; but as this latter is found only to the north, whilst the G. 

 virginianum occurs in almost every part of the country, this latter has been 

 selected as a type of the properties of the genus. 



G. virginianum, Linn. — Pubescent, stem erect; lower leaves ternate, petiolate; upper 

 ones sessile and simple ; folioles ovate-lanceo- 

 late, acute, unequally serrate ; stipules mostly Fig. 141. 

 toothed; awns of carpels uncinate, hairy, 

 twisted. 



Linn., Sp. Fl. 500; Torrey and 

 Gray, Fl. i. 421 ; Rafinesque, Med. 

 Fl. i. 220 ; G. canadense, Jacquin, 

 Hort. ii. t. 275. 



Common Names. — White Avens; 

 Throatroot ; Bennet ; Chocolate-root. 



Description. — Root perennial, small, brown, 

 contorted, horizontal. Stem erect, about two 

 feet high, simple, pubescent, few-flowered. 

 Radical leaves on long petioles, without sti- 

 pules ; lower stem leaves furnished with large 

 stipules, but on shorter petioles ; upper leaves 

 sessile, simple, resembling the folioles of the 

 lower leaves, which are oval or ovate-lanceo- 

 late, acute at base, and acuminate, deeply 

 and unequally serrate. The flowers are ter- 

 minal, white, on erect peduncles. Calyx 

 sub-campanulate, deeply five-cleft, with five 

 exterior alternate bracteoles. Petals five, 

 yellowish-white, shorter than the calyx, and 

 inserted into it. Stamens numerous, short, 

 unequal ; filaments filiform, anthers roundish 

 and yellow. Styles numerous, long, hairy, 



G. virginianum. 



