( ^3 ) 
Long-leaved Great Pondweed, with pellucid leaves; 
In rivers. The leaves of this plant vary, fome of 
them being broad and others narrow. 
3. Potamogitm folio angufto pellucido fore gramh 
neo^ R. 148. Pondweed, with narrow pellucid leaves. 
This refembles the former, but is lefs in all its parts, 
the leaves not exceeding four inches in length. The 
upper leaves grow by pairs, but thofe below alter- 
nately. 
4. Potarnogiton ferfoliatim^ R. 149. foliis latis^ 
fplendentibus^ C. 193. P otamogiton 3. Dodon^i^ G. 
E. 822. Perfoliate Pondweed. In rivers. This plant 
lies generally under water, with only its top above : 
The leaves are broad, thin, oblong, pointed and pel- 
lucid, encompafling the ftalk with their bottoms. It 
has no thin membranes furrounding the ftalks and 
branches, like thofe of the firft fpecies. 
5. Potamogiton rotundifoUum alterum^ R. 149, 
Round-leaved Pondweed. 
6. Potamogiton feu Fontalis media lucenSy R. 149, 
foliis crifpis feu Ladluca ranarutiiy C. 193. Fribulus 
aquaticus minor Mufcatell^ floribuSy G. E. 823.. aquat. 
minor alter y P.124-8. The Leffer Water Caltrops, 
or Frogs-lettuce. In rivers. The leaves are pellu- 
cid, oblong, finuated, and curled about the edges;. 
This fpecies differs remarkably from the reft, in ha- 
ving its leaves placed by pairs upon the ftalk. 
7. Potamogiton feu Fontalis crifpa^ R. 149. foliis 
crifpis feu Labluca ranarmiiy C. 193,. Fribulus aqua- 
ticus minor Fluercus floribuSy G. E.. 824. aquat. minor 
priory P. 1248. The Greater Water Caltrops. In 
rivers. The leaves grow alternately •, they are about 
two inches long, and half an inch broad, fo much 
curled and finuated round the edges, that they feem 
to be jagged, 
8 . Potamogiton caule compreffoy folio Graminis cam- 
niy R. 149. Small branched Pondweed, with a flat 
ftalk. In rivers. The leaves are long and narrow, 
refem- 
