POTAMOGETON. 
439 
ci/ofivs, ed. viii. (not Wolf g.).' — St. slightly branched. Snb- 
mersed 1. with a few additional parallel veins next midvein, 
subsessile. Floating 1. often wanting. Fed. long, slightly 
thickened upwards. In river Boyne near Xavan. [r. Lawne, 
Killorgliu. P:dley Fen, Hunt.?.] P. ' E. I. 
10. P. heterophyl' I US (Schreh.) : submersed I. lanceolate nar- 
roiced at both ends sessile minuteb/ denticulate and apiculatCy 
floating 1. subcoriaceous elliptic stalked, stip. broadly lanceolate 
blunt irith 2 stout prominent ribs, lower ones linear-lanceolate, 
fr. blunt on the back, peduncle thicker than the stem sirelhn'j 
'ufnrards.—E. B. 1285. E. vii. 41 — 43. St. much branched 
below. Submersed 1. wavy. Lower stip. without the two 
strong ribs and equally veined, upper ones widely spreading. 
Dry fr. slightlv marked with 3 ridges on the back. — Ponds 
and ditches. P. YI. VII. E. S. 1. 
11. P. nitens (TVeb., sec. Xolte) ; submersed I. lanceolate 
rounded below and half clasping wavy at the edge, floating 1. 
" coriaceous elliptic stalked," stipules equally veined, (drj-) fr. 
keeled, ped. swelling upwards. — R. vii. 34. S>j- E. B. 1407. 
./. of B. ii. t. 23. — St. rather wavy, branched below. Subm. L 
pellucid, often rectirved ; upper 1. often not coriaceous. Upper 
stip. large, persistent, nearly | as long as the peduncle. Dry 
fr. with 3 ridges on the back. [Mr Fryer considers tliis a series of 
hybrids P. graminij'oliu^y: ptrjoiiatus, P. heterC'phylluixpfTfoliatus andP. aiigusti- 
jolius xperfeiiaius, and writes " rarely fruiting, with 1 or 2 drupelets on a spike, 
probably resulting from a chance fertilization by allieri species."] — Lakes 
near Brandon Mountain, Kerry (P. curinfolius Hartm.). 
Loch Ascog. Bute. River Tay, Perth. Coltneld. Elsrin, ic. 
P. VII. virt. "E. S. I. 
12. P. falaitus (Fryer); submersed 1. sessile eiliptical strap-slmped o/ttn not 
•ittite itftntnetTical with somewhat rounded base, the upper amplexicaul, the margin 
entire slightly undtilatcd, floating 1. stalked elliptic mucronate coriaceous, stip. 
herbaceous persistent upper broad, fr. small rhomboidal-OToid acutely keeled with 
distinct lateral ridges, ped. thicker than the st. scarcely swoUen upwards usually 
shorter than the 1. — J. of B. xsTii. (1889) p. 65, t. 2S6.— St. branched from near 
the base.— Fsn ditches, Hunts P. VI. VII. E. 
13. P. var'ians (Morong ex Fryer); submersed 1. sessile or shortly stalked 
narrowly lanceolate usuaUy flat, floating 1. stalked oval or more or less spathulate 
apiculate coriaceous, stip. herbac-rous persistent narrow bluntish, fr. -small 
nearly circular flattened very acutely keeled with prominent lateral ridges, beak 
short, ped. slightly thicker than the st. not tluckentd upirards from the 'jase of the 
1 Mr Ley's plant from Sellack which according to tlie Author s ilS. is probably 
P. salicifolivs, is considered by Mr Fryer to be a hybrid of unknown origin. 
-H. & J. G. 
