CXLT. EllIOCAULACE^. 841 



Order CXLV. ERIOCAULACE^. 



Annual or perennial scapigerous marsli (rarely aquatic) herbs. Leaves 

 narrow, with sheathing bases ; veins parallel. Plowers 1-sexual, usually 

 monoecious, minute, mostly white, densely aggregated in a solitarj'- 

 globose or hemispheric head at the apex of a peduncle with a tubular 

 basal sheath ; heads androgynous (rarely 1-sexual), with an involucre 

 of short 2-many-seriate imbricate scarious or chartaceous bracts, often 

 radiating beyoud the circumference of the ilowering part of the head ; 

 the florets often more or less hoary with short white hairs, and closely 

 packed on a flat, convex, hemispheric, or conical receptacle, each floret 

 solitary in the axil of a cuneiform bract which equals or exceeds its 

 floret, and is usually dorsally hoary near the apex (rarely absent). 

 Corolla usually separated from the calyx by a distinct stipes, sometimes 

 rudimentary, especially in the male flowers (rarely absent). Male 

 FLOWERS : sepals usually 3, free or conuate, deciduous (rarely 2 or 0). 

 Petals usually 3, connate in a stipitate funnel-shaped miuufcely 3-lobed 

 corolla, one lobe sometimes longer than the others. Stamens 6 or fewer, 

 iusei'ted on the corolla ; filaments short, often unequal ; anthers 

 didymous, 2-celied, usually black. Pistillode or reduced to minute 

 glands. Eemale flowers sessile or stipitate. Sepals 2-3 (rarely 1 or 

 0), unequal, usually concave, deciduous. Petals usually 3, unequal, 

 broad or narrow, often ciliate or hairy, frequently with a dark glandular 

 spot on the inner face. Ovary superior, sessile or stipitate, globose, 2- 

 3-celled ; ovary solitary in each cell, pendulous ; style-branches 2-3, 

 filiform. Pruit a small membranous 2-3-celled loculicidal capsule. 

 Seeds minute, oblong, ellipsoid or globose, smooth, striate, or ribbed ; 

 albumen floury ; embryo minute. — Distrib. Genera 9, according to 

 Euhland [Monog. Eriocaul. in Eugler, Pflanzenreich, v. 4, part 30 

 (1903)] ; species about 370, in the warmer regions of both hemispheres, 

 most numerous in Tropical America, few in temperate regions. 



1. ERIOCAULON, Linn. 



Marsh or aquatic herbs ; stem usually very short or 0, rarely elongate. 

 Leaves linear, membranous, often fenestrate. Male and female flowers 

 generally mixed in the same, rarely in separate heads. Male elowers : 

 Sepals 2-3, free or often more or less united into a split spathe (rarely 

 absent). Petals 2-3, at the apex of the tube, sometimes with a black 

 gland on the inner face, sometimes rudimentary or absent. Stamens 

 twice as many as the petals or by abortion fewer ; anthers 2-celled, 

 usually black. Pemale flowers : Sepals usually free, mostly unequal, 

 concave, boat-shaped or flattened, often bearded on the apical part 

 or cihate. Petals 2-3, always free (rarely absent), often with a black 

 gland on the inner face a little below the apex. — Distrib. Warmer 

 parts of both hemispheres in marshy places, North Asia, China, Japan, 

 N. America, Africa, Australia, one species in the British Isles, otherwise 

 absent from Europe ; species about 200. 



Aquatics ; stems elongate, floating, branched. 



Leaves capillary, 1-nerved 1. E. setacemn. 



Leaves linear, -l-T-nerved... 2. E. rivulare. 



