oS 3, each 2-lobed. Seeds numerous, fixed to three parietal placenta. — Aquatic 
450 HYDROCHARIDACEJE. (FROG'S-BIT FAMILY.) 
Orper 140. HYDROCHARIDACEUE.  (Fnoc's-piT 
: Famivy.) d 
Aquatic herbs, with monecious or diccious flowers, from a membrana- 
ceous spathe. Sepals and petals 3, or the latter wanting, distinct in the - 
sterile flower, united into a tube in the fertile, and coherent with the 1-9- 
celled ovary. Stamens 3-12. Ovules numerous, ascending, orthotropous. 
Stigmas 3-9. Fruit indehiscent, many-seeded. Embryo straight, without 
albumen. 
Synopsis. 
* Ovary l-celled. Stigmas 3. 
1. ANACHARIS. Flowers polygamo-diccious. Spathe sessile. Stamens 9. Leaves short, 
opposite or whorled. : : 
2. VALLISNERIA. Flowers dicecious. Spathe peduncled. Stamens 3. Leaves long; linear. 
* * Cells of the ovary and stigmas 6-9. " 
3. LIMNOBIUM. Flowers monccious. Stamens 6-9, monadelphous. Leaves cordate 
petioled. ; 
1. ANACHARIS, Rich. 
Flowers diceciously polygamous, enclosed in the bud in a 2-cleft axillary 
sessile spathe. Sterile flowers minute. Sepals and petals 3.  Anthers 9. Fer- 
tile flowers pistillate or perfect. Sepals and petals united into a very long and 
slender 6-parted tube. Stamens 3-6, perfect or sterile. Ovary 1-celled, with 
three parietal placentz, few-ovuled. Style capillary, adnate to the tube. Stig- 
mas 3, each 2-lobed, exserted. Fruit oblong, coriaceous. — Perennial herbs, 
with elongated filiform branching immersed stems, and small and very numer 
ous opposite or whorled leaves.  Fertilization effected by the sterile fime 
breaking away from the stem, and expanding at the surface among the floating 
stigmas. 
1. A. Canadensis, Planch. Stem much branched; leaves 3-4 in ® 
whorl, sessile, varying from linear to elliptical, I-nerved, pellucid and ern 
serrulate. (Udora Canadensis, Nutt.) — In slow-flowing streams and ponds, 
Cherokee, North Carolina, Curtis, and northward. July and Aug.—149 
3”- 6” long. - 
2. VALLISNERIA, Micheli. TAPE-GRASS. 
- Flowers dicecious. Sterile flowers numerous, minute, crowded on ? spadix, 
which is enclosed in an ovate 3-leaved short-stalked spathe. Calyx 3 
Corolla none. Stamens 3. Fertile flowers solitary, enclosed-in a tubular $ ^ 
and borne on a very long and mostly spiral scape. Sepals and small pet? 
united and coherent with the cylindrical 1-celled many-ovuled ovary. s 
