FOTAilOGETON. 
441 
denticulate, nearly sessile, with very short stalks. Stip. green, 
lanceolate, with -2 narrow wings on the back. Ped. 6 — 8 in. 
long, much thicker than the stem. Spike 1 in. long ; 11. rather 
more whorled than as rejiresented in E. B. S. Fr. unknown. — 
Deep water. Found floating loose in Lough Corrib, Galway. 
[Mr Frver ivfei-3 thi^ Co P. i 'icois ;ind Mr Bennett to /' ' c ■ ?■ ' ' u '.'Hi.] 
P. xii\. I. 
18. r. p)XHl<yn'<ji(s (Wulf.) ; I. pellucid ohloay-ianvroiatt. half' 
• !.<pinij blunt and hooded at the end entire, stip. not winged, fr. 
k 'eled on the back when fresh keeled or winged vhen dry, pe- 
duncle very long equal, spikes many-flowered. — E. B. S. 2858. 
vii. ,3.3. — St. long, growing in deep water. L. with parallel 
V ins adjoining the midrib. Peduncles 6 — 12 in. long. Spikes 
1 — 2 in. long. — Rivers and ditches, rare. P. V. VI. E. S. I. 
19. P. peifolidtus (L.) ; st. round, I. j)ellucid rordate-ovate or 
ovate-lanceolate clasping not hooded, fr. rounded on the back 
when fresh keeled when dry, peduncle equal. — E. B. 168. R. 
vii. 29. — St. long, slightly branched, rather dichotomous at the 
top. Peduncles rather thick and short. Spikes short. — [a stata 
with 1. elongate almost lanceolate has been r-ferred to var. hinaolatvs (Blytt).] — 
Lakes and streams. P. VII. E. S. I. 
20. P. cris'pv.s (L.) ; st. compressed, I. peHucid linear-oblong 
blunt sessile serrate wavy,//-, with a long beak keeled on the 
back when dry [base of keel with a long projecting tooth, A. F?y<r], 
peduncle equal.— ^. B. 1012. P. vii. 29— 30.— St. much 
branched. Ped. long. Spikes few-flowered. Beak as long as 
the nut. L. usually crisped at the edges, occasionally flat (P. 
Serratus L.). [p. Coepen (Fryer) is P. cri.'pvs-AperJijUctv.s and P. Bcnnettii 
(Fryer) is P. crispusyiobtusijMd<s^ — Ditches and Streams, p. VI. 
E. S. L 
*** L. all submersed, alternate, linear-ligulate ; stipides free. 
21. P. comjji-es sus (L. sec. Fr.) ; st. flattened, /. linear-acumi- 
nate with ^principal and ma n >/ close parallel intermediate veins 
occupying the whole surface, spikes cylindrical ttpon long ]>ed., 
sep. transversely oval, fr. obovate keeled, style terminal. — 
E. B. S. 2685. P. vii. 27. P. zosterifolius (Schum.). P. 
cuspidatus (Sm.). — Ped. 2 — 4 in. long. Spikes 10-^15-flowered. 
Inner edge of fr. rounded ; faces a little convex. L. suddenly 
acuminate or apiculate. — Rivers and lakes. P. \I. E. 8. 
22. P. acutifolius (Link, in R. k S.) ; st. flattened, linear- 
acuminate 7oith 3 jivincipal and manij close parallel intermediate 
cet HS occupying the whole suvfa.cG, spike$o''ateabmttas long as the 
short ped., sep. rliomboidal, fr. broadly ^f-obovate compressed 
