TR he Meets MEI lad i 
SAGITTARIA AND LOPHOTOCARPUS., 43 
ricate, 15 to 35 mm. long, exceeding the sterile; stamens 
15 to 21; achenium 2 mm. long, narrowly winged on both 
margins and costate from the base of the beak above, sub- 
epidermal resin passages usually present; fruiting head 10 
to 12 mm. in diameter; seed obovate, 1 mm. long, the 
seed-coat punctate. — Margins of shallow ponds, from 
western Kansas and eastern Colorado south to Texas, New 
Mexico and Sonora. — Plate 11. 
Specimens examined from Kansas (Kellerman, Gove Co., 1885; Hitch- 
cock, 1892, in Ford, Seward and McPherson counties) ; Oklahoma (Carle- 
ton, 262, 1891, Cherokee Outlet); Colorado (Iendler, 850, 1847, Arkansas 
R.; Beckwith and Gunnison, 49, Upper Arkansas R.); Texas (Lind- 
heimer, June, 1847, Pierdenales; Wright, 680, and 1140, 1849); Mexico 
(Palmer, 1889, Lerdo, Sonora, specimens with winter tubers attached). 
S. GREGGII n. sp. 
Monoecious, stout, erect, 10 to 14 dm. high; leaves 20 
to 40 cm. long, the lanceolate, acuminate, widely divergent 
basal lobes longer than the lanceolate or ovate and acumi- 
nate middle one; scape erect, 5-angled below, paniculately 
branched from the lowest verticils, exceeding the leaves; 
branches slender, striate, ascending; verticils numerous, 
the lower fertile; bracts lanceolate, acuminate, 15 to 25 mm. 
long; fertile pedicels 15 to 30 mm. long, about as long as 
the sterile; sepals minutely scabrous; stamens 30 or more, 
4to 5mm. long; fruiting heads globose, 8 to 15 mm. in 
diameter; achenium 2 to 3 mm. long, tumid crested on 
both margins, from obovate with the ventral margin nearly 
straight to almost circular, edges acute, sides with an irreg- 
ular saucer-shaped wing, and more or less tubercled; seed 
1 mm. long, smooth.—In ponds and ditches, California and 
Mexico. Collected by J. A. Sanford, July 1893, Stock- 
ton, Cal. 
The species is dedicated to Dr. J. Gregg, whose No, 833, 
collected in May 1849, at Zamora, Michoacan, Mexico, 
seems to be the same as our Californian plant. — Plate 12. 
§§ Fluitantes: Leaves floating or submerged; fertile pedicel or pedicels 
thickened and reflexed in fruit, longer than the sterile; bracts at first 
17 
