HKLIANTIIUS — aUNFLOWKU. 1 7i) 



An jinnual l)raiu'luii<^ herb 1 to 3 foct high, hairy or roup^hiHli-pulK's- 

 ceut. LoavoH b' iimatilul, the lippeiino.st. simply piiinatifid, siaoothish or 

 plabrous above, Aw or whiiiwh bo'iioatb. 



Habitat. — In waste places every where ; a niont pestiferous ■weed. 



Parts Uned. — The leaves and tops — not oliicial. 



Constifucnts. — Both species have a disagvoeablo odor and an aromatic 

 bitter taste. The leaves of ^1. trijida are readil} eaten l)y si)me of the do- 

 mestic animals, but the other species appears to bo too disa^'reeable. Their 

 constituents have not been ascertained. 



Preparations. — They arc commonly used in decoction. 



Medical Properties and Uses. — These plruts are said to be stimulant, 

 tonic, and astringent. A decoction has been us(h1, chiefly in domcf tic prac- 

 tice, as a topical astringent in chronic catarrhal atl'ections. 



Of late years A. artemiaia'fulia has attracted considerable attention on 

 account of its real or assumed agency in the production of hay-fever. The 

 plant produces pollen in groat abundance, which is extremely irritating to 

 the air-passages of many people, and is callable of exciting asthmatic at- 

 tacks in Huscei)tiblo pei'sons. Now as the weed is so very abundant, and 

 its time of flowering coincident with the greatest development of hay-fever, 

 the relation of cause and efltect has been asserted by many writers. Tliat 

 it may be so in a certahi proportion of cases is cpiite probable, but that its 

 influence in this direction has been overrated is still more probable. The 

 pollen of all plants is irritating to the air-passages of sensitive people, but 

 probably little more so than any other dust of an oi-ganio character ; and 

 the proportion which rag-weed pollen in the air of any specitied locality 

 bears to that of all other plants combined must be very small indeed. 

 Much less still must its proportion be to other pollen and organic dust 

 in the air of cities, where this allection has become endemic — and fashion- 

 able. 



HELIANTHUS. —Sunflower. 



Helianthus annuus Linne. — Common /Sunflower. 



Description. — Heads lai'ge, many-flowered, radiate ; the raj'S numerous, 

 neutral, yellow ; the disk-flowers brownish, perfect. Scales of the invo- 

 lucre with foliaceous tips, imbricated in 3 or more series. lle(X'ptacle 

 broad and flat, with persistent chatf which embraces the 4-angl'id, flattened 

 achenia. Pappus very deciduous, of 2 chafiy scales on the principal 

 angles of the achenium, often with two or more smaller intermediate ones. 



A tall rough annual herb, in common cultivation. Leaves alternate, 

 triple-ribbed, ovate, or the lower cordate. 



Habitat. — The sunflower is a native of tropical America, but has long 

 been cultivated here and is sparingly naturalized in waste places. 



Many of the indigenous sijecies of helianthus are but little less strik- 

 ing than this in appeai'ance, and possess similar properties. 



