COMPOSIT.E. (COMPOSITE FAMILY'.; 189 



62. Achillea.! Involucre with imbricated bracts aa in the last, but campanulate or obo- 

 vate. Chatfy hracts of the receptacle menibraiiaceous, like the innermost brai ts of the 

 involucre. Rays few or several, short and broad, Akene.i ol.long or obovute, obcoin- 

 pressed, glabrous, destitute of pappus. 



♦ « Receptacle destitute of bracts or chaff, 

 t- Heads radiate, pedunculate, solitary at the sunmiit of the branches, or sometimea corj-m- 



bose. 

 G3. Matricaria.2 Receptacle conical or ovoid, or rarely lower wlien young. Akenes 3 to 

 5-ribbed or nerved on the face or sides, rounded on the back, 

 ■t- ••- Heads discoid. 

 G4. Tanacetum. Heads corymbosely cyniose or glomerate, rarely solitarj', many-flowered ; 

 female flowers with tubular 3 to 5-toothed corolla. Akenus .')-ribl)ed or:j to i-aiigiilar. 

 with broad truncate summit, bearing a corouiform i>appu3 or none. Antlicr-tips 

 broad and mostly obtuse. 



65. Artemisia. Heads puniculately disposed, few to many-flowered, small, heterogamous, 



the female flowci-s with small and slender tubular corolla, and the lieru)aphnMlit« 

 either sterile or fertile ; or homogamous, with the flowers all hermapiirodite and fer- 

 tile. Antlier-tips slender and pointed. Akeues obovate or oblong, destitute of 

 pappus. 



Tribe VIII. SENECIONIDE^E. Involucre mostly one or two series of equal bracts, 

 sometimes uneciual or imbricated, with or without accessory ones at base. Leaves 

 usually alternate. Chiefly distinguished by the copious capillary pappus, simple in- 

 volucre, and naked receptacle. 



* Involucre a series of soft herbaceous bracts : heads subdioecious, racemosely or corj'm- 



bo.sely disposed, whitisli flowered: herbs with ample mostly radical leaves. 



66. Petasites. Akenes narrow, 5 to 10-costate, with elongating soft and white pappus. 



♦ ♦ Involucre lax (not erect-connivent), of much overlapi)ing bracts (4 or 5), many- (at 



least 20-) flowered: herbs with opposite leaves. 



67. Haploesthes. Heads radiate ; flowers all fertile. Involucre short-campanulate, of 



similar rather flesiiy orbicular or broadly oval bracts, the outer strongly ovcrlapi'ing 

 the inner. Ligules of the rather few and short ray-flowers oval. Akenes line^ir, terete, 

 striate-costate, glabrous. Pappus a single series of rather rigid and scabrous whitish 

 bristles. 



• « ♦ Involucre of 4 to 6 firm and concave close and strongly overlapping bracts, 4 to 9- 



flowered : shrubs, with alternate leaves. 

 6S. Tetradymla. Heads homogamous. Involucre cylindrical to oblong. Corollas with 

 lanceolate or linear spreading lobes. Anthers wholly exserted. Akenes terete, short, 

 obscurely 5-nerved, from extremely long-villous to glabrate or even glabrous. Pappus 

 of fino and soft minutely scabrous capillary long bristles, white or whitish. 



♦ * * « Involucre of numerous 'or several connivent-erect herbaceous equal bracts, many- 



flowered : herbs, with opposite or alternate leaves. 

 39. Arnica. Heads conspicuously radiate, or the rays rarely wanting. Invi>lu<*re r.im- 

 pauulate, of several thin-herbaceous oblong-lanceolate to linear equal bracts in a single 



1 The Old-World genus Anthemis has a naturalized species within our range and may Ik- 

 characterized as follows : — 



Anthemis. Involucre hemispherical, many-flowered, of comparatively small imbricated 

 bracts, the outer successively shorter. Chaffy bracts of rcccptJtcle sometimes hyaline, some- 

 times aristiform. Akenes terete or 4 to 10-anglcd or ribt)ed, not flattened, glabruus ; the 

 tr mcate summit naked, or with a very short coronil'orm or auriculate paj)pus. Head« 

 comjiaratively large — See p. 198. 



2 The following Old-World genus has a naturalized species within our liordcrs : — 

 Chrysanthemum. Recei>tacle from flat to hemisphericjil. Akenes (at legist of the dUk) 



5 to 10-ribbed or uerved all round. — See p. 199. 



