Lappa. COMPOSITE. 463 



subulate and spreading, with the rigid apex uncinate. Receptacle flat, some- 

 what fleshy, selose-fimbrillate. Corolla regularly 5-cleft, lO-nerved. An- 

 thers tipped with filiform appendages, caudate at the base : filaments papil- 

 lose. Branches of the style free and divergent at the apex. Achenia ob- 

 long, compressed, glabrous, rugose transversely. Pappus of numerous short 

 filiform scabrous bristles, not united into a ring, caducous. — Biennial branch- 

 ing coarse (European) herbs; with large cordate and petioled leaves with 

 slightly undulate margins, the lower surface more or less tomentose. Heads 

 small, solitary or somewhat corymbose. Corolla purple varying to white, 

 equalling the involucre. — Burdock. 



1. L. major (Gsrtn.) : scales of the involucre all subulate and with unci- 

 nate tips, either glabrous or loosely arachnoid ; upper cauline leaves ovate ; 

 the others (large) cordate. — Gcerin. Jr. 2. p. 379, t. 162. L. major & 

 L. minor, DC. prodr. 6. p. 661. Arctium Lappa, Linn.; Darlingt. fl. 

 Cest. p. 436. 



Fence-rows and waste-places in rich soil : introduced from Europe. — A 

 troublesome weed, well known under the name of Burdock. Dr. Darling- 

 ton and Mr. Tuckerman have observed an occasional form, (L. Bardana ?) 

 with pinnatifid leaves. 



Suborder II. LABIATIFLOR.E. DC. 



Corolla of the perfect flowers bilabiate ; the outer lip mostly 3-lobed 

 or 3- toothed, and the inner 2-cIeft or 2-toothed. Pollen smooth, glo- 

 bose or elliptical. 



Tribe VL MUTISIACEiE. Less. 



Heads heterogamous, or rarely dioecious ; the marginal flowers pis- 

 tillate or neutral, either ligulate or bilabiate. — Style nearly as in the 

 Cynareae. 



175. CHAPTALL^. Vent. hart. Cels. t. 61 ; DC. in ann. mus. 16. p. m. 



Heads many-flowered, heterogamous, radiate ; the rays pistillate and fer- 

 tile, in 2 series; the disk-flowers perfect, but sterile by the abortion of the 

 ovary. Corolla of the outer series of ray-flowers simply ligulate, or rarely 

 with a minute inner lip ; of the inner series filiform and much shorter than 

 the style, obliquely truncate, the inner lip rudimentary ; of the disk-flowers 

 bilabiate, the lips equal in length, the outer 3-toothed, the inner 2-parted. 

 Scales of the campanulate involucre imbricated in few series, linear, acute, 

 1-nerved. Receptacle naked. Anthers caudate. Achenia of the fertile 

 flowers oblong, glabrous, striate, attenuate at each end, somewhat beaked, 

 and with the apex slightly dilated ; of the disk-flowers abortive. Pappus 

 copious, capillary, minutely scabrous. — Perennial acaulescent (American) 



