1234 CAEDUACEAE 



sessile or some of them partly clasping : flower-clusters less than 1 cm. in diameter : invo- 

 lucres campanulate, 2-3 mm. high : bracts various, those of staminate flowers spatulate, 

 those of pistillate flowers oblong or oval, all cottony at the apex : staminate flowers with a 

 vestige of a pistil. 



In dry or stony soil, Georgia to Texas and California. Introduced eastward. Spring and summer. 



2. Filago prolifera (Nutt. ) Britton. Stems 2-20 cm. high, simple or branched at the 

 base, often with 2-6 simple or proliferous ascending branches at the summit: leaf -blades spatu- 

 late, 5-14 mm. long, obtuse : flower-clusters over 1 cm. in diameter : involucres fusiform 

 orcylindric : bracts various, those of staminate flowers herbaceous, woolly at the apex, those 

 of pistillate flowers firmer, glabrous or nearly so : staminate flowers with slender stipe-like 

 abortive pistils. 



In dry soil, South Dakota to Arkansas and Texas. Spring and summer. 



59. CALYMMANDRA T. & G. 



Small caulescent plants resembling species of Filago. Leaves alternate : blades broad- 

 ened upward. Heads in closely sessile bracted or somewhat involucrate clusters, heterog- 

 amous. Involucre of few scarious externally woolly bracts which grade into the bractlets 

 of the disk. Receptacle hemispheric. Pistillate flowers in several series, fruit-producing, 

 each with slender truncate corollas. Perfect flowers 5, central, fruit-producing, each enclosed 

 in a convolute woolly bractlet, with a somewhat inflated 4-lobed corolla. Anthers sagittate 

 at the base. Achenes broadened upward, obscurely obcompressed, glabrous. Pappus 

 wanting. 



1. Calymmandra Candida T. & G. Foliage silvery white with appressed woolly 

 hairs. Stems 1-4 dm. tall, simple or much branched from the base : leaf-blades spatulate, 

 1-3 cm. long, entire : heads solitary or clustered in the axils : involucres campanulate, 

 1.5-2 mm. high : bracts including those of the pistillate flowers narrowly oblong-spatulate, 

 densely woolly without : achenes about 0.5 mm. long, smooth. 



In dry soil, Texas. Spring and summer. 



60. GIFOLA Cass. 

 Annual caulescent herbs, resembling species of Filago. Leaves alternate : blades en- 

 tire, conunonly sessile. Heads discoid, in small dense sometimes proliferous clusters. In- 

 volucres narrow, sessile : bracts scarious, in several series. Eeceptacle subulate to obconic, 

 chaffy. Pistillate flowers marginal, fruit-producing, each with filiform corollas and rudi- 

 mentary or no pappus. Perfect flowers central, few, each with tubular corollas and several 

 scabrous hair-like pappus-bristles. Between the pistillate and perfect flowers are some 

 similar to the marginal, but with pappus like the central. Anthers sagittate at the base. 

 Achenes terete or slightly flattened. [Filago L. 1758; not L. 1753.] Cudweed. 



i; Gifola Germanica (L. ) Dumort. Foliage silvery with dense woolly pubescence. 

 Stems commonly branched at the base, 5-35 cm. tall, proliferous above, or rarely simple : 

 leaves numerous ; blades erect, lanceolate to linear, 1-2 cm. long, acute : heads numerous, 

 in dense globular clusters : involucres oblong or ovoid-oblong, 3 mm. high: bracts ovate- 

 lanceolate to oblong-lanceolate, acuminate to cuspidate : achenes about 0.8 mm. long. 



In dry soil or waste places, New York to Georgia. Naturalized from Europe. Spring to fall. 



61. PLUCHEA Cass. 

 Annual or perennial caulescent herbs, or shrubs. Leaves alternate : blades usually 

 toothed, often prominently nerved, petioled, or the upper sessile or clasping. Heads dis- 

 coid, commonly in cluster-like cymes. Involucres turbinate, hemispheric or campanulate, 

 with pistillate and perfect flowers : bracts broad, in few series. Receptacle flat, naked. 

 Pistillate flowers marginal, fruit-producing. Perfect flowers central, mostly not fruit-pro- 

 ducing. Anthers sagittate, the auricles tailed. Stigmas united or distinct. Achenes 4- 

 5-angled. Pappus a single series of scabrous hair-like bristles. Marsh Feeabane. 



Plants perennial. 



Leaf-blades entire : stems woody. 1. P. odorafa. 



Leaf-blades toothed : stems herbaceous. 



Outer bracts of the involucres acuminate. 2. P.foetida. 



Outer bracts of the involucres obtuse or merely acute. 



Pappus white : upper stem-leaves little shorter than the lower. 3. P. lotipifoHa. 



Pappus bulY : upper stem-leaves much shorter than the lower. 4. P. imbricata. 



