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. FLEXUosus. Nutt. (A. sparsiflorus. PA.) Few-fiowered Aster. 



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

 lower ones sublanceolate-linear, upper ones subulate; brancJies 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. LiNiFOLius. (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 hds. mi- 

 nute. — 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. arjpiKos, silken, Kapno;, fruit; from the character of the genus. 



Heads few-flowered; ray-flowers 4 — 6,9; disk-fls. 6 — 10, 5; in- 

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

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

 simple. — % Herbs with alternate leaves and close corymbs. Rays white. 



1. S. soLiDAGiNEUs. Nccs. (Astcr 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 Da. Not common. 

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

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

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



2. S. coxVYzoiDEs. Nees. (Aster. Wllld. Conyza asteroides. Linn.) 

 (S/!. 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, obtu.se, appressed, slightly reflexed at summit; rays 5, short, 

 — Common in woods and thickets, Mass. to Flor. Stems somewhat 5-an^led, 

 1 — 2fhigh. Leaves somewhat fleshy. Ray short, but longer than the disk,' 

 white. July, Aug. 



12. DIPLOPAPPUS. Cass. 



Gr. <J(7rXooj, double, Tran-TTos, 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. e?itire^ alternate. Mays cyanic. Disk yellow. 



1. D. LiNARiiFOLius. Hook. (Astcr linariifolius. Linn.) 



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

 bricate, carinate, as long as the disk ; lvs. linear, entire, 1-veifted, mucronate, 

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

 in dry woods, alung streams, U. S. and Can., rather rare. Stems sub.simplc| 

 purplish, abcnit a fuot high, decumbent at ba.se. 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. UMBELLATu.s. Hook. (k. amygdalinus. Michx. A. umbellatus. Ait.) 

 St. smooth, straight, simple; coiymb fastigiate; lvs. 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 drv fields but 1—2), 



