CAEDUACEAE 1271 



corollas yellow or purplish brown. Anthers entire at the base. Stigmas linear-lanceolate. 

 Achenes of the disk more or less flattened, margined or barely winged, truncate or notched. 

 Pappus of several scales between the chaffy teeth or awns. The plants flower in summer 

 and fall. 



Leaf-blades linear or linear-lanceolate : involucral bracts appressed : ray-flowers 16-20. 



1. H. grandiflora. 

 Leaf-blades linear-filiform : involucral bracts spreading : ray-flowers 10-15. 2. H. tenuifolia. 



1. Helianthella grandiflora T. & G. Stems 6-12 dm. tall, simple or sparingly 

 branched. Leaves mostly alternate ; blades linear or slightly tapering, 2-6 cm. long, 

 acute, entire, somewhat revolute : heads showy : involucral bracts linear-subulate to lan- 

 ceolate or lanceolate, or oblong with lanceolate tips, hispidulous, the tips rather lax : 

 ray -flowers 16-20 ; ligules yellow, 3-4.5 cm. long : disks 1.5-2 cm. broad : achenes 5 mm. 

 long, wing-margined, pubescent about the upper edge, each side surmounted by a tooth, and 

 one or both prolonged into an awn. 



In pine lands, Florida. 



2. Helianthella tenuifolia T. & G. Stems 3-8 dm. tall, simple or corymbosely 

 branched above : leaves alternate or opposite, or whorled on the lower part of the stem ; 

 blades linear-filiform, 3-8 cm. long, acute, entire, revolute, very scabrous : heads showy : 

 involucral bracts linear-subulate to linear-lanceolate, attenuate, spreading : achenes 4- 

 angled, 3 mm. long, minutely pubescent, the margins prolonged into triangular scales. 



On sand hills, Florida. 



99. ZEXMENIA Llave & Lex. 



Perennial caulescent herbs or shrubby plants. Leaves opposite, or rarely alternate : 

 blades simple. Heads radiate, often showy. Involucres campanulate or hemispheric : 

 bracts in several series, relatively broad, dry, the outer sometimes broader than the rest 

 and spreading. Keceptacle flat or convex, chaffy. Kay-flowers pistillate, fruit-producing : 

 ligules yellow. Disk-flowers several, perfect, fruit-producing : corollas yellow. Anthers 

 entire or slightly sagittate at the base. Stigmas of the disk with acute pubescent appen- 

 dages. Achenes various ; those of the ray and edge of the disk 3-angled, the others 

 more or less flattened, sometimes winged. Pappus of 1-3 awns, these sometimes accom- 

 panied by several distinct or partially united scales. 



1. Zexmenia hispida (H.B.K.) A. Gray. Stems strigose or strigose-hispid, 

 branched at the base ; branches 2-7 dm. long. Leaf -blades rhombic to lanceolate, acute 

 or acuminate, repand-serrate, somewhat cuneate at the base, sessile : peduncles elongated : 

 heads rather showy : involucres 6-7 mm. high ; bracts lanceolate in the outer series, ob- 

 long to ovate in the inner, acute or acuminate : ray-flowers with orange-yellow ligules 

 about 1 cm. long : disk barely 1cm. broad : achenes obovate, winged. 



In dry soil, Texas and adjacent Mexico. 



100. ACTINOMERIS Nutt. 



Perennial caulescent rough-pubescent, rather coarse herbs. Leaves alternate or oppo- 

 site : blades simple, more or less toothed, usually decurrent on the stem. Heads radiate or 

 discoid. Involucres small, of few spreading or recurved narrow bracts. Eeceptacle con- 

 vex or conic, becoming globose, chaffy. Ray-flowers neutral, or wanting : ligules yellow 

 or white. Disk-flowers perfect, fruit-producing embraced by the bractlets. Anthers entire 

 at the base. Stigmas of the disk with acute appendages. Achenes flattened, more or 

 less winged. Pappus of two finally spreading awns, these sometimes accompanied by 2-3 

 smaller awns or scales. The plants flower in summer and fall. 



Ray-flowers 2-8 : disk-corollas yellow. 1. A. alterntfolia. 



Ray-flowers wanting : disk-corollas white. 2. A. paniculata. 



1. Actinomeris alternifolia (L.) Britton. Foliage finely pubescent. Stems 6-25 

 dm. tall, winged, corymbose above : leaf -blades oblong or elliptic, 1-3 dm. long, acuminate 

 at both ends, serrate : heads rather showy : involucres flattish ; bracts linear to linear- 

 lanceolate, acute : ray-flowers 2-8: disks 1-1.5 cm. broad : corollas yellow, 5 mm. long : 

 achenes obovate, 5-6 mm. long, winged : pappus of 2, or in the case of marginal achenes 3, 

 awns. 



In thickets and rich soil, New York to Iowa, Florida and Louisiana. 



2. Actinomeris paniculata ( Walt. ) Small. Foliage scabrous, but barely pubescent. 

 Stems 6-24 dm. tall, corymbose above, becoming smooth : leaf-blades linear to oblong or 



