170 COMPOSITiiE. 



3. G. nemoralis Nees. : stem pubescent, roilgh, 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 

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

 A. ledif alius Pursh. 



Sphagnous swamps. Can. Mass. and N. J. Sept., Oct. ^i-. — 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-flbwered. (G. nemoralis, P.monoceplialus D.C. Aster uniflorus 

 Mich.) Wood Galatella. 



13. SERICOCARPUS. iVees.— Sericocarpus. 

 (From the Greek trripiKos, silky, and Kapiros, 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 hnear, 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. 



Dry swamps and woods. Can. and N. S. to Louis. ; rare. Aug., Sept. %. — 

 Plant yellowish-green. Stem about 2 feet high, often several from the same 

 root, slender, nearly simple or with a few short branches near the summit. 

 Heads iew, 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 

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

 each end, ciUate ; 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. %.^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 i3 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. Cas5.— Diplopappus. 

 (From the Greek JtirXooj, double, and na-mroi, 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- 



