170 COMPOSITE. 



3. G. nemoralis Nees. : stem pubescent, rough, corymbose at the summit ; 

 leaves lanceolate-linear, entire, without nerves or punctures, scabrous and 

 somewhat revolute on the margin ; scales of the involucre linear, acute, in 

 tew series, much shorter than the disk ; rays elongated. A. nemoralis Ait. 

 A. kilifolius Pursh. 



Sphagnous swamps. Can. Mass, and N. J. Sept., Oct. ^. Stem simple, 

 12 18 inches high, fragile and thickly set with leaves which are sometimes 

 minutely bidentate. Heads large ; rays pale violet. The stem is sometimes 

 simple and 1-flowered. (G. nemoralis, /?. monocephalus D. C. Aster uniftorus 

 Mich.) Wood GalateUa. 



13. SERICOCARPUS. Nees. Sericocarpus. 



(From the Greek <njfo; , silky, and /capu-oj, fruit ; the achenia being very silky.) 

 Heads 12 15-flowered ; the ray flowers about 5 ; those of 

 the disk tubular, fertile. Involucre imbricate, ovate or oblong ; 

 the scales in several series, broad at the base, cartilaginous, 

 nerveless, the upper part herbaceous and often spreading. Re- 

 ceptacle small, alveolate ; the alveoli toothed or lacerate-ciliate. 

 Achenia obpyramidal, short, densely strigose-silky. Pappus 

 of simple, rigid, rough bristles. 



1. S. solidagineus Nees.: smooth; stem erect, somewhat flexuous, an- 

 gled with elevated lines ; leaves linear-lanceolate or linear, attenuate at the 

 base, obtuse, the margin scabrous, obscurely 3-nerved ; corymb fastigiate ; 

 scales of the oblong involucre squarrose at the tips ; rays elongated. 

 Conyza linifolia Linn. Aster solidaginoides Willd. 



Heads few, somewhat clustered in a fastigiate corymb ; rays 3 8, white, longer 

 than the disk. Pappus white. Narrow-leaved Sericocarpus. 



2. S. conyzoides Nees : stem slightly pubescent, a little angular ; leaves 

 elliptic, or oval-lanceolate, obscurely 3-nerved, smooth beneath, acute at 

 each end, ciliate ; lower serrate towards the apex, narrowed to a petiole at 

 base ; involucre oblong-turbinate, the scales squarrose at the tips ; rays 

 short. Conyza asteroides Linn. Aster conyzoides Willd. 



Woods and copses. Mass, to Flor. July Sept. 1J.. Stem 1 2 feet high, 

 rigid, but rather slender, Heads few, in small clusters. Scales whitish at base, 

 green at the tip. Var. plantaginifolius Nees. (Aster conyzoides plantaginifolius 

 Nutt.), has the radical leaves spatulate, the heads somewhat pedicelled,and the 

 rays about as long as the involucre. Broad-leaved Sericocarpus. 



14. DIPLOPAPPUS. Cass. Diplopappus. 

 (From the Greek <5t?rAoo? , double, and natt-tos, pappus.) 



Heads many-flowered ; ray flowers in a single series, pistil- 

 late ; those of the disk tubular, perfect. Receptacle flat, some- 

 what alveolate. Involucre imbricate. Achenia oblong, com- 



