3* 26. Pofcamogit. 6. FLUVIAT. Pl.end.pk . 
3. Potamogiton fluitans. Floating riuerweed . 
Upper leaves floating, lanceolate oval, narrower at both 
ends ; peduncles long ; lower leaves under water, linear, 
lanceolate acute. 
Pot. natans (3, Poiret Enc. Meth. 5, 579. 
Pot. fluitans , Roth FI. Ger. J, 72. 
Ponds and rivers ; perennial ; August and September. 
Root creeping; stem flat, very long; branches , leafy; 
leaves reddish green, finely veined, alternate; sheath wide, 
spearshape ; spike dense, reddish. 
b. Leaves all of one sort . 
4. Potamogiton lucens. Shining river weed a 
Leaves ovate, lanceolate, fiat, ending in a short petiole, 
shining, veined; stipules the length of the joints; spikes 
many flowered, crowded. 
P. aquis immersum, folio pellucido lato oblongo acuto, Raii Syn. 148,2., 
P. longis acutis foliis, Ger. ern. 822. 
P. lucens, Lin. S. P. 183. 
Running and stagnant waters; perennial ; June, July. 
Plant keeps under water, with only the spike above the 
surface ; flowers reddish ; stipules embracing the stem, 
leaflike. 
angustifolium . Leaves narrow ; plant smaller. 
P. folio angusto, pellucido, fere gramineo, Raii Syn. 148, 3. 
y. nudum . Leaves ovate, lanceolate ; petioles scarcely 
margined. 
5. Potamogiton crispum. Crisp riverweed. 
Leaves lanceolate, alternate, sessile, waved, serrate ; 
stipidee with the tip torn and ciliate; stem slightly com- 
pressed. 
Pot. sen Fontinalis erispa J. Bauhini, Raii Syn. 149, 7. 
Tribulus aquaticus minor, quercus floribus, Ger. em. 824. 
Pot. crispum, Lin . S. P. 183. 
Greater water caltrops . 
Ponds and slow running waters ; perennial ; June, July. 
Leaves sunk, obtuse ; peduncles sunk ; spike fewflowered ; 
flowers reddish, remote. 
j3. serratum . Leaves serrated ; upper leaves opposite. 
6. Potamogiton lanceolatum. Spearshape riverweed . 
Leaves linear, lanceolate, flat, not nicked, verrucose, 
broader than the stipulse, narrow at the base; peduncle 
thickened, shorter than the leaves; spike ovate, dense, 
fewflowered. 
