Anacharis. ■ HYDRUCHAKIDACE.-E. 129 



Class II. MONOCOTYLEDONOUS or ENDOGENOUS PLxVNTS. 



Stems with the woody fibres scattered irregularly, not forming a separate zone 

 of annual woody layers between the bark and pith. Embryo with one cotyledon. 

 Leaves mostly parallel-veined, alternate, entire, and sheathing at base. Floral 

 whorls usually in threes, 



ORDER CIV. HYDROCHARIDACE^. 



Aquatic herbs, with dioecious or polygamous flowers in membranous spathes ; 

 re-ular 6-parted perianth, in two series (calyx and corolla), more or less tubular at 

 bale • stamens 3 to 12 ; ovary inferior, 1 - several-celled, with ascending ovules on 

 parietal placenta.; fruit indehiscent ; and seed without albumen. -Distinguished 

 from the ^aiadacece and allied orders mainly by the inferior ovary. Perianth more 

 or less tubular at base. Staminate flowers usually several and pedicelled : stamens 

 distinct or united, the 2-celled anthers mostly introrse. Pistillate flowers usually 

 sohtary : style single : stigmas 3 to 6, more or less deeply bifid. Fruit submerged, 

 a utricle or berry, usually many-seeded. Mostly perennials, with radical or m our 

 species opposite or whorled leaves. 



A widely distributed order, of a dozen genera and perhaps 30 species, very sparingly repre- 

 sented in North America, and especially so on the western coast. 



1. ANACHARIS, Richard. Water-weed. 

 Flowers polygaino-dioecious, solitary and sessile in an axillary sessile tubular 

 2-cleft spathe. Perianth small, in the sterile flowers with 3 scarcely united greemsh 

 sepals and as many narrower petals ; in the pistillate flowers with a greatly elon- 

 gated filiform tube and a 6-parted spreading limb. Stamens 3 to 9, with short 

 filaments united at base ; anthers oval, or in the pistillate flowers oblong or want- 

 incr Ovary 1-celled, with 3 parietal placentae, few-ovuled. Style coherent with 

 the perianth-tube: stigmas 3, bifid or emarginate. Fruit a subglobose utricle.— 

 Slender perennials, with elongated leafy branching stems, and numerous opposite or 

 whorled sessile thin 1-nerved leaves ; two or three temperate or tropical species. 



1 A Canadensis, Planchon. Stems very slen.ler and brittle, 1 to 4 feet 

 long, te;ete, rooting at the nodes : leaves dark gree.i and pellucid, in ^l^^'^^^^ °J ^^Tv 

 or the lower opposite, linear- or lanceolate-oblong, 3 to 6 lines long acute, minu^y 

 serrulate, sessile: tube of the perianth in the pistillate A"--^ ^ to 8 inc^^ o^^^^ 

 limb 11 to 2 lines in diameter, greenish-purple; sepals concave, P f "^ ^ \^^;^;;^ 

 stigmas long, terete, emarginate: utricle included within the siua ^^f-^ 

 spathe, nearly a line in diameter, ^ - G-seedech - Ann^ c^ Mag. ^^'t" I^^^^.^^^^^^' 

 i. 8G. Modea Canadensis, Michx. ; Caspary, Hydrill. 8G & 123. L do, a, .Nutt. 



In-Mendocino Connty (Vasey) ; Oregon (ffall, (rou.m^n.<^iniA^Ai^ 

 ponds and slow streams, and naturalized «?jtensn^ely in Emoi^ m sM^^^ 

 have rarely been noticed, are described as breaking from t^^^,^*^™^''^^^^^^^^^^^^^ 

 upon the surface of the water, to which the pistillate are raised by the elongated peuantu 



