Subclass Il MONOCOTYLEDONS: those whose embryos have a 
single cotyledon; the stems with more or less scattered fibro-vascular- 
bundles; the leaves usually parallel-veined; and the flower usually 3- 
merous. 
HYDROCHARIDEZ. (FRO0G’s-BIT FAMILY.) 
Aquatic herbs, with dicecious or polygamous regular flowers (sessile or 
on seape-like peduncles from a spathe), single or double floral envelopes 
united into a tube (in the fertile flowers) and coherent with the 1 to 3- 
celled ovary, 3 to 12 distinct or monadelphous stamens with 2-celled 
anthers, 3 to 6 stigmas, and the many-seeded indehiscent fruit ripening 
under water. 
. *Ovary l-celled: stigmas 3. 
1. Blodea. Stems elongated, submerged: leaves verticillate (rarely opposite): 
perianth-tube long filiform. 
2. Vallisneria. Stemless, grass-like, submerged: leaves elongated: fertile flowers 
solitary on a very long scape. 
* * Cells of the ovary and stigmas 6 to 9. 
3. Limnobium. Stemless, floating: leaves broad, long-petioled. 
1. ELODEA Michx. (WaATER-WEED.) 
Perennial herbs, with elongated branching stems, numerous whorled 
or opposite sessile leaves, polygamo-dicecious sessile solitary flowers 
from a sessile tubular 2-cleft axillary spathe, the minute sterile flowers 
with 3 sepals and petals and 9 stamens, fertile flowers pistillate or per- 
fect with perianth extended into an extremely long tube with 6-parted 
limb, 3 to 9 stamens, capillary stvle adnate to the tube, 2-lobed or 
notched exserted stigmas, and an oblong coriaceous few-seeded fruit. 
1. BE. Canadensis Michx. Leaves in 3s or4ds, or the lower opposite, varying from 
linear to oval-oblong, minutely serrulate: stamens 9 in the sterile flowers, 3 or 6 
almost sessile anthers in the fertile. (Anacharis Canadensis Planchon,)—Slow streams 
and ponds. 
2. VALLISNERIA L. (Tape-Grass. EbL-GRAsS.) 
Submerged stemless plants, with grass-like leaves, moncecious flow- 
ers, the sterile numerous and crowded in a head on a conical recepta- 
cle enclosed in an ovate at length 3-valved spathe which is borne on a 
very short scape and with mostly 3 stamens, the fertile solitary and 
sessilein a tubular spathe upon an elongated scape, the linear perianth- 
tube coherent with the 1-celled ovary, 3 large nearly sessile 2-lobed 
stigmas, and elongated cylindrical berry-like fruit. 
11874—No. 3——6 
421 
