ZANNICHELLIACEAE 15 
Famity 1. ZANNICHELLIACEAE — Ponpweep FAMILY 
Aquatic caulescent herbs. Leaves alternate, filiform or with broad entire 
us 
oe 
distinct earpels. .Fruit a cluster or spike of drupelets. —Five genera and 
bout 80 species, most abundant in temperate regions. 
Flowers monoecious, axillary : leaves opposite. Tribe I. ZANNICHELLIEAE. 
Flowers perfect, borne in stalked clusters or spikes : leaves al- 
ernate. Tribe II. RUPPIEAE. 
I. ZANNICHELLIE 
eer a herbs, the very slender leaves with c 
stipu 1. ZANNICHELLIA. 
RUPPIEAE 
Stamens 2 or sometimes solitary, the connective without ap- 
pendages: drupelet manifestly stipitate. 2. RUPPIA. 
eee 4, the connective with dilated appendages : drupelet 
sile. 3. POTAMOGETON. 
1. ZANNICHELLIA [Mich.] L. Delicate herbs of fresh or brackish 
water. Leaves with narrow blades and inconspicuous bases. Flowers mo- 
noecious: staminate with 1 stamen: pistil- l 
late with 2-6 carpels together. Drupelets 
clustered, curved, crested.—Two or three 
species, widely distributed. | 
1. Z. palustris L. Stem 2-7 dm. a Pao 
2-7 em. P acute: drupelets 
sometimes 6, together, the body E mm. 
long, short stipitate.—( ORNED-PONDWEED.) 
—Ponds, Pod and p throughout 
S. a 
—(W. I., C. A. 
)— — Oft ten in pos mats 
just beneath the c of the water. 
2. RUPPIA L. Delicate herbs of salt or brackish water. Leaves with 
slender blades and conspicuous bases. Flowers perfect. Stamens 2. ele 4, 
Drupelets clustered, oblique, crestless.—Thre 
or four species, very widely distributed. 
ritima is Stem 3-10 dm. long: 
(W. i654 s 
—Sum.-fall.——Commonly in exten- 
d dense masses just beneath ae dpa 
the water. In the extreme souther | 
Coastal Plain the plant may be coal in ihe winter. 
3. POTAMOGETON [Tourn.] L. Herbs growing mostly in fresh water. 
Leaves various, the submerged and floating mainly different. Flowers perfect, 
spicate. Stamens 4, with appendaged anthers. Carpels 4. Drupelets 4 to- 
gether, spicate, sessile—About 70 species, widely distributed in temperate 
