DipLopaprvs. LXXV. COMPOSITZ. 325 
a reading anicle of heads which are below the middle size and furnished 
with snow-white rays. July—Sept. 
41. A. ruexvuosus. Nutt. (A. sparsiflorus. Ph.) Few-flowered Aster. 
St. branching, slender, flexuous, very smooth; Jvs. 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, 1f high, with large, purple flowers; disk yellow. Aug.—Oct. 
42, A. LINIFoLIUS. (A. subulatus. Michx.) Sea Aster. 
St. paniculate, much branched from the base; dvs. long, linear, very acute, 
the uppermost subulate; zvol. 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. onptxos, silken, kap7os, fruit; from the character of the genus. 
Heads few-flowered ; ray-flowers 4—6, 2; disk-fls. 6—10, $; 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. soxrpacineus. Nees. (Aster solidaginoides. Michz. 
Smooth; lvs. linear-lanceolate, obtuse, entire, sessile, obsoletely 3-veined, 
rough on the margin; corymd 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 green tips. Rays long, white. Jl. Aug. 
2. S. conyzoipes. Nees. (Aster. Willd. Conyza asteroides. Linn.) 
St. somewhat pubescent, simple, corymbose at top; ls. 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. eylindri- 
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. dimdoos, double, tats, pappus; from the character. 
Heads many-flowered: ray-fls. about 12, 2; disk-fls. $; involucre 
imbricate ; receptacle flat, subalveolate ; pappus double, the exterior 
very short, interior copious, capillary; achenium compressed.—2. 
Lws. entire, alternate. Rays cyanic. Disk yellow. 
1. D. tinarurotivs. Hook. (Aster linariifolius. Linn.) 
St. straight, roughish ; branches 1-flowered, fastigiate; scales of invol. im- 
bricate, carinate, as long as the disk; dvs. linear, entire, 1-veined, mucronate, 
earinate, 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. umpBeLuatus. Hook. ee amygdalinus. Michx. A. umbellatus. Ait.) 
St. smooth, straight, simple; corymd 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 1—2), 
