DIPLOPAPPUS. LXXV. COMPOSITE. 325 



a spreading panicle of heads which are below the middle size and furnished 

 with snow-white rays. July Sept. 



41. A. FLEXUOSTJS. Nutt. (A. sparsiflorus. PA.) Few-flowered Aster. 



St. branching, slender, flexuous, very smooth ; Irs. long and succulent, the 

 lower ones sublanceolate-linear, upper ones subulate; branches leafy, 1-flow- 

 ered; invol. scales lanceolate, acuminate, appressed; rays numerous, shorter 

 than the involucre. Grows in salt marshes, Mass, to Flor. The whole plant 

 very smooth, If high, with large, purple flowers; disk yellow. Aug. Oct. 



42. A. LINIFOLIDS. (A. subulatus. Michx.) Sea Aster. 



St. paniculate, much branched from the base ; Ivs. long, linear, very acute, 

 the uppermost subulate ; invoL cylindric with subulate scales ; radical Ms. mi- 

 nil te. An annual species, found in salt marshes, Mass, to Car. Stem 12 18' 

 high, very smooth, thick, reddish. Leaves smooth, sessile. The plant is very 

 Branching, with numerous short-rayed, small, purple flowers. Aug. 



11. SERICOCARPUS. Nees. 

 Gr. aijptKOS, silken, KO^TTOJ, fruit; from the character of the genus. 



Heads few-flowered; ray-flowers 4 6,9; disk-fls. 6 10, $; in- 

 volucre oblong, imbricated ; scales appressed, with green, spreading 

 tips ; receptacle alveolate ; achenium obconic, very silky ; pappus 

 simple. ^i- Herbs with alternate leaves and close corymbs. Rays ivhite. 



1. S. SOLIDAGINEUS. Nees. (Aster solidaginoides. Michx.) 



Smooth ; Ivs. linear-lanceolate, obtuse, entire, sessile, obsoletely 3- veined, 

 rough on the margin ; corymb fastigiate ; hds. aggregate, subsessile, 5-rayed ; 

 scales obtuse, white, with green tips. In woods, Can. to La. Not common. 

 Stem slender, simple, about 2f high. Leaves smooth, pale green, 1 2' by 3 

 5". Heads rather small, in a level-topped corymb. Involucre oblong. Scales 

 imbricate, appressed, with conspicuous gr.een tips. Rays long, white. Jl. Aug. 



2. S. coNYzolDEs. Nees. (Aster. Willd. Conyza asteroides. Linn.') 



St. somewhat pubescent, simple, corymbose at top ; Ivs. oval-lanceolate, 

 smooth beneath, slighly 3-veined, narrowed at base, acute, the upper ones ses- 

 sile, nearly entire, the lower narrowed into the petiole, serrate ; invol. cylindri- 

 cal, the scales oval, obtuse, appressed, slightly^reflexed at summit; rays 5, short. 

 Common in woods and thickets, Mass, to Flor. Stems somewhat 5-angled, 

 1 2f high. Leaves somewhat fleshy. Ray short, but longer than the disk, 

 white. July, Aug. 



12. DIPLOPAPPUS. Cass. 



Gr. JiTrAooj, double, namros, pappus; from the character. 



Heads many-flowered: ray-fls. about 12, 9; disk-fls. $; involucre 

 imbricate ; receptacle flat, subalveolate ; pappus double, the exterior 

 very short, interior copious, capillary ; achenium compressed. % 

 Lvs. entire, alternate. Rays cyanic. Disk yelloio. 



1. D. LINARIIFOLIUS. Hook. (Aster linariifolius. Linn.} 



St. straight, roughish ; branches 1 -flowered, fastigiate ; scales of invol. im- 

 bricate, carinate, as long as the disk; lis. linear, entire, 1-veined, mucronate, 

 carinate, rough, rigid, those of the branches recurved. A handsome species' 

 in dry woods, along streams, U. S. and Can., rather rare. Stems subsimple^ 

 purplish, about a foot high, decumbent at base. Leaves numerous, rigidly up- 

 right or recurved, obtuse, with a small, mucronate point, pale beneath, shining 

 above. Branchlets near the top, leafy, each with one rather large and showy, 

 violet-colored head. Aug. Sept. 



2. D. UMBELLATUS. Hook. (A. amygdalinus. Michx. A. umbellatus. Ait.) 

 St. smooth, straight, simple ; corymb fastigiate ; Ivs. long, lanceolate, 



smooth, attenuate-acuminate at each end, rough on the margin ; invol. scales 

 obtusely lanceolate. A tall, handsome plant, growing in low grounds, river 

 banks and fields. N. Eng. to La. Stem 3 4f high (in dry fields but 12). 



