HYDROCHARITACEAE | 29 
narrowly conie, rae 1 cm. long: sepals green, oval to ovate, 3-4 mm : 
o white, 9-11 mm. long: pistillate flowers not seen Lakes, Pinellas pen., 
— Perhaps introduced through cultivated plants.—(S. A.) 
FAMILY 2. HYDROCHARITACEAE — Fnoc's-Brr FAMILY 
Plants with leaves in clusters on the rootstocks. Gynoecium 6-9- 
pellary, ie ovary 6—9-celled.—Comprises 8 genera and about 20 ¢ species of 
: temperate and tropieal regions. 
"Flowers ue Men distinct : anther nearly sessile: leaf not differentiated 
: intó. e and petio 1. THALASSIA. 
; Flowers monoecious: com mens with united filaments: leaf differ- 
l o blade and petiole. 2. LIMNOBIUM. 
1. THALASSIA Banks. Marine herbs. Leaves mere strap-like blades. 
Flowers dioecious. Fruit rugose or nearly echinate.— Two species, circum- 
tropical. | 
1. T. testudinum Koenig & Sims. Leaves 
-2—5 together; blade linear, 5-30 em. long: 
fruit . echinate-pubescent, 'erect.— ( TURTLE- 
)—Bays a 
RASS -WEED nd coasts, pen VANN | 
Fla. and Florida Reef.—( ,8. À4 All RNY M 
ear.— in vast submarine AN 
I 
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EXE 
aX goa 
= SS 
el f ^ 
= 
SS 
d 
= 
~~ 
—_ 
e 
co 
X 
<— 
=e 
=~ 
sate 
often f 
leaves are washed n Ed vast quantities 
Co 
Tr 
Qe 
> 
=g, 2 
rd do. 
Aad 
a 
e pe eR : 
I pte ETE. 
E. S Dt e 
MM 
AM 
and are gathered as ‘‘s eed?! for ferti- Sn 
lizer. Only during quiet puc and con- | 
i clear water, can one get an p ee 
of these DIR rine fields 
Hades rendezvous for various Nn a fish, turtles, Ed other marine animals. 
2. LIMNOBIUM L. C. Rich. Fresh-water herbs. Leaves with dilated 
blades terminating petioles. Flowers monoecious. Fruit smooth. Three or 
four species, American, 
1. L. Spongia (Bose.) L. C. Rich. Leaves 
several i eee us ovate : suborbi- 
ular niform oad: fruit 
pre nodding ems s- Ed .) Shallow 
water and mud, various provinces, Fla. to 
ex., Mo., Ont., and N. J.—Sum —fa ll.—T he 
plants are very variable in size, 
leaves vary shape and have short or long 
petio In marshes as bs water dries up 
ioles. - 
js frog’s-bit grows rapidly and often 
overs acres of these low lands with a peer 
been carpet. 
OrpER POALES — PoAL ORDER 
Mostly perennial caulescent or acaulescent plants, known as grasses 
and sedges. Stems sometimes conspicuously jointed. Leaves alternate, 
mostly sheathing at the base: blades usually narrow and elongate, entire or 
nearly so. Flowers variously disposed in a simple or compound inflores- 
cence, perfect or rarely monoecious or dioecious, incomplete, inconspicu- 
ous, borne in the axils of chaffy bracts or scales (glumes). Fruit a cary- 
opsis (grain) or an achene, or rarely a nut, or baceate. 
