336 COMPOSITE. Actinomeris. 



§ 2. Receptacle very small, subglobose : scales of the involucre few in a single 

 scries, at length reflexcd : achenia usually broadly ivinged : rays none : 

 disk squarrose in fruit : the corolla white. — Anactimeris. 



2. A. alba : stem smooth and glabrous, or scabrous-puberulent at the 

 summit, often slightly winged above ; leaves alternate, narrowly lanceolate, 

 tapering to each end, slightly petioled, serrate, scabrous ; heads in a loose 

 corymb ; scales of the involucre lanceolate-subulate ; achenia crowned with 

 2 slender awns. — A. squarrosa, var. alba, Nutt. I. c: Ell. ! I. c. Verbesina 

 Coreopsis /3. alba, Michx. ! I. c. ; Pursh, I. c. ; Atlianasia paniculata, Walt. 

 Car. p. 201. 



Alluvial soil (tec, S. Carohna to Western Louisiana ! Aug.-Oct. — Stem 

 3-10 feet high. Leaves 5-8 inches long ; the lower ones very sharply ser- 

 rate ; the upper often decurrent, but frequently not at all so. Heads smaller 

 than in A. squarrosa. Chaff ovate-lanceolate, shorter than the flowers,_ 

 membranaceous. Achenia with a very broad white wing ; which is fre- 

 quently so large that the transverse diameter of the fruit is twice as great as 

 the longitudinal ; while some of the achenia, even in the same head, are 

 nearly or quite wingless : the awns longer than in the preceding species, and 

 the corolla with a more deeply cleft limb. 



§ 3. Receptacle conical : scales of the involucre in 2-3 series, not spreading 

 or reflexcd in fruit: rays 8-15, regular: achenia slightly winged : flowers 

 yellow: stem {and sometimes even the peduncles) conspicuously ivinged with 

 the decurrent alternate leaves. — Pterophyton, Cass, (partly.) 



3. A. helianthoides (Nutt.) : stem hirsute-pubescent; leaves alternate, 

 ovate-lanceolate, acute, serrate, closely sessile, canescently villous with soft 

 appressed hairs beneath, strigose-scabrous above ; heads few in a contracted 

 simple corymb; peduncles mostly wingless ; rays 10-14, long and narrow; 

 achenia crowned with 2 setiform awns. — Nutt. ! gen. 2. p. 181 ; Ell. sk. 2. 

 p. 413,- DC! prodr. 5. p. 575, ^-7. p. 290. (a. Nuttallii & /?. EUiottii !) 

 Verbesina helianllioides, Miclix. ! I. c. 



Thickets, and in prairies, Ohio ! Illinois ! and Missouri ! to the western 

 part of Georgia! Louisiana! and Arkansas! June-Jnly. — Stem 2-4 feet 

 high. Leaves about 3 inches long and one or more broad, acute or attenu- 

 ate-acuminate. Scales of the involucre canescent, lanceolate, oval, or some- 

 what spatulate. Rays narrowly lanceolate, 18-20 lines long, golden yellow. 

 Corolla of the disk deep yellow, with an elongated throat, 5-toothed. An- 

 thers conspicuously appendlculate. Chaff rigid, lanceolate, longer than the 

 fruit. Achenia oval, pubescent; the awns rather short, very slender, fragile, 

 — The plant cultivated in the Geneva garden has much broader involucral 

 scales than we have observed in indigenous specimens. The habit is quite 

 different from the other N. American species : the disk does not become squar- 

 rose ; and the receptacle is almost like that of Rudbeckia. A. ovata, and A. 

 tetraptera, DC. c^c. apparently belong to this section. 



§ 4. Receptacle at length conical: scales of the involucre few, in 2-3 series, 

 not spreading or reflexcd in fruit ; the exterior lanceolate, much shorter than 

 the disk; the innermost resenMing the chaff: rays 7-12: achenia usually 

 wingless, with short awns : flmvers yelloio : leaves closely sessile, mostly op- 

 posite, not at all decurrent. — Apteron. 



4. A. nudicaulis (Nutt.) : scabrous-hirsute ; stem wingless, paniculately 



