eriocatjlonace^. (pipewoet family.) 549 



Order 126. EBI0CAVL,0NACE.;E. (Pipewort Family.) 



Aquatic or marsh herbs, stemless or short-stemmed, with a tuft of fibrous 

 roots, a cluster of linear and often loosely cellular grass-like leaves, and 

 naked scapes sheathed at the base, bearing dense heads of monceclous or 

 rarely dioecious small 2 - Z-merous flowers, each in the axil of a scarious 

 bract; the perianth double or rarely simple, chaffy; anthers introrse; the 

 fruit a 2 - 3-celled 2 - 3-seeded pod : the ovules, seeds, embryo, &c. as in 

 the preceding order. — Chiefly tropical plants, a few in northern temper- 

 ate regions. 



1. E^rlocaulon. Perianth double, the inner (corolla) tubular-funnel-form in the stamlnate 



flowers ; the stamens twice as many as its lobes (4 or 6). Anthers 2-cellecl. 



2. Peepalantliufi. Perianth as in the last : the stamens only as many as the lobes of the 



inner series, or corolla (3). Anthers 2-celled. 



3. Lacliiiocauloii* Perianth simple, of 3 sepals. Stamens 3, monadelphous below. An- 



thers iKielled. 



1. EKIOCAIJLON,' L. Pipewoet. 



Flowers moncecious and aadrogynous, i. e. both kinds in the same head, eitlier 

 intermixed, or the central ones sterile and the exterior fertile, rarely dicecious. 

 Ster. Fl. Calyx of 2 or 3 keeled or boat-shaped sepals, usually spatulate or 

 dilated upwards. Corolla tubular, 2 -3-lobed, each of the lobes bearing a black 

 gland or spot. Stamens twice as many as the lobes of the corolla, one inserted 

 at the base of each lobe and one in each sinus : anthers 2-celled. Pistils rudi- 

 mentary. Fert. FL Calyx as in the sterile flowers, often i-emote from the rest 

 of the flower (therefore perhaps to be viewed as a pair of bractlets). Corolla 

 of 2 or 3 separate narrow petals. Stamens none. Ovary often stalked, 2-3- 

 lobed, 2 -3-celled, with a single ovule in each cell: style 1 : stigmas 2 or 3, 

 slender. Pod membranaceous, loculicidal. — Leaves mostly smooth, loosely cel- 

 lular and pellucid, flat or concave above. Scapes or peduncles terminated by a 

 single head, which is involucrate by some outer empty bracts. Flowers, also 

 the tips of the bracts, &c., usually white-bearded or woolly. (Name compounded 

 of epiov, wool, and kouKos, a stalk, from the wool at the base of the scape and 

 leaves of the original species. Excepting this and the flowers, our species are 

 wholly glabrous. ) — The North American species are all stemless, with a 

 depressed head, and have the parts of the flowers in twos, the stamens 4. 



1. E. decangul^re, L. (syn. Pluk. &c.) Leaves obtuse, varying from 

 linear-lanceolate to linear-awl-shaped, rather rigid ; scapes 10-12-ribbed (1°- 

 3° high; head hemispherical, becoming globular (2" -7" wide); scales of the 

 involucre acutish, straw-color or light brown ; chaff (bracts among the flowers) 

 pointed. (E. serdtinum. Wait.) — Pine-barren swamps (New Jersey ?) Virginia, 

 and southward. July - Sept. 



2. E. gnaphal6des, Michx. Leaves spreading (2'-5'long), grassy-awl- 

 shaped, rigid, or when submersed thin and pellucid, tapering ^adually to a 

 sharp point, mostly shorter than the sheath of the lO-ribbed scape; scales of the 

 involucre very obtuse, turning lead-color ; chaff obtuse. (E. decangulare, L., in 



