Sagittaria.} NAIADACEAE. 457 
1. SAGITTARIA, L. 
Flowers unisexual. Perianth of 3 outer herbaceous wraiiiiee and 3 larger 
inner ones petal-like and very delicate. Stamens numerous. Carpels 
umerous in a dense globular head, each with a basilar erect ovule. — 
Leaves long-stalked, usually cordate or hastate. Flowers in a racemé or 
narrow panicle, the lower ones female or hermaphrodite, the upper male. 
A genus rd bce species, dispersed over the northern hemisphere and extending into 
South Amer 
Th: 8. Se I. — Kunth, Enum. Pl. IIT, 156. — Micheli, in De 
Cand. Monogr. IIT, 66. — Rhizome thick tuberous, stoloniferous. Leaves 
on long petioles of 1—2 ft., ot the basal lobes 4—5‘ long, diverging, 
acute. Scape exceeding iis lea owers monoecious, in whorls of 3 
r e upp 
lanceolate, 3—4”, Sepals reflexed. Petals white, 3—4‘. Stamens in- 
definite; the anthers linear, basifixe s long as the eiabiicess filaments. 
Carpels very numerous, Sabon. planta winged when mature 
Style 2 erect or curve 
In Oo» -ponds of ajitent, near Honolulu! a late arrival. The species ranges 
over the whol le of Europe, middle « and southern Asia to Java, and in America extends 
from Canada to southern Mexico. Th the sake of the tuber. 
Orver XCIII. NAIADACEAE. 
Flowers usually proceeding from a small gota bract. Perianth 
wanting or of 4 small scale-like segments. Stam 4. Ovary 
either of 2 or 4 distinct carpels, each with a sees po and a separate 
stigma, or single, with 1 ovule and 2—4 stigmas. Fruit of 1, 2 or 4 seed- 
like nuts, each with 1 seed, without albumen. — Aquatic floating or sub- 
merged herbs. Leaves either sheathing at the base or accompanied by 
sheathing stipules, alternate or rarely opposite. Flowers axillary, incon- 
spicuous, solitary or in spikes. 
An Order not numerous in species, dsr — diffused over all parts of the world, 
- ato W seas as we: ell as in fresh v 
fa cingle anther; 
apm a axillary, 
. fl. of arpel . Pe te NH A ek 
“Soe hermaphrodite, -spica 
Perianth wanting; stamens nyt ovary of 4 carpels, long stipitate 
Ww 2. Ruppia. 
hen fpcmweg 
Perianth ot 4 segments; stamens and carpels 4, the latter sessile 
mature : ; A A : 2 : : : : 3. Potamogeton. 
1. NAIAS, L. 
Flowers unisexual. Male fl. with a double perianth, the outer (spathe?) 
tubular, entire or 2—4-cleft, the inner hyaline, adnate to the anther. 
n 1, the sessile anther 1—4-celled. Fem. fl. a single ovary, naked 
