" LYTHRUM. HALORAGE. 217 
HIPPURIS. 
cesses; petals 4, caducous; stamens 4; style very short or none; capsule 
4-celled. On wet banks, along the Columbia River and the Eastern States. 
2 LYTHRUM Juss. Gen. 132. 
Herbs, rarely suffrutescent plants, with opposite or scat- 
tered entire leaves and purplish or white flowers. Calyx cylin- 
‘drical, striate, with 4-6 short lobes and usually as many inter- 
mediate teeth or processes. Petals 4-6. Stamens as many or 
twice as many as petals, inserted on the tube of the calyx. 
Style filiform: stigma capitate. Capsule oblong, 2-celled, many- 
seeded, enclosed in the calyx-tube. 
L. adsurgens Greene Pitt. ii, 12. Stems 1-‘ feet long, from a stoloni- 
ferous perennial base, stoutish but tough and flexible, 5-angled, decumbent 
or nearly prostrate, herbage pallid and glabrous: leaves scattered, linear, 
sessile: calyx 2-3 lines long the small lobes subulate, the intermediate 
processes broad and mucronulate: petals pale purple, but little exceeding 
the calyx-lobes. In wet or springy places, Puget Sound to California. 
OrpdeER XXXVII. HALORAGEA Endl. Gen. 1155. 
Herbs or suffruticose plants growing in water or wet places 
with various leaves and small axillary sessile perfect, rarely 
monececious or dicwcious flowers. Limb of the calyx 3-4-lobed or 
entire, sometimes wanting. Petals 3-4 small or wanting.  Sta- 
mens as many or twice as many as the lobes of the calyx, some- 
times fewer, inserted with the petals into the summit of the 
calyx. Ovary coherent with the calyx, 1—-4-celled, witha solitary 
pendulous ovule in each cell. Styles 1-4 or none: stigmas as 
many as cells of the ovary, distinct. Fruit dry and indehiscent. 
Seeds anatropous with a straight embryo and thin fleshy albu- 
men. 
* Stamens one. 
1. Hippuris. Ovary 2-celled: leaves verticillate, linear or oblong, entire. 
2. Callitriche.. Ovary 4-celled: leaves opposite, linear or spatuiate, 
entire. 
* * Stamens 5-8. 
3. Myriophyllum. Ovary 4-celled: leaves verticillate subvert cillate or 
scattered, the emersed entire toothed or pectinate, the submerged pin- 
natifid. 
1 HIPPURIS. L. Gen. n. 11. 
Aquatic perennial herbs with simple stems, verticillate entire 
leaves and minute axillary flowers. Flowers perfect, or by 
abortion sometimes neutral or pistillate. Calyx-tube adherent 
-to the ovary, the limb minute, entire. Petals none. Stamen 
one, inserted on the margin of the calyx. Style filiform, stig- 
matic its whole length and lying in a groove of the stamen. 
Fruit 1-celled, 4-seeded. 
H. vulgaris L.Sp.i, 4. Stems erect, 10-20 inches high, rather stout: . 
leaves in whorls of 6-12, linear, 8-12 lines long or more, one-nerved: 
