THE FLOE A OF WARWICKSHIRE. 
263 
b. decipiens , Nolte. Very rare. 
Canal, Warwick, Sept., 1882, R. L. Baker. “Dr. Baker’s plant 
approaches my var. affmis very closely, the only difference 
being that the spikes are longer than in Mr. Brotherston’s 
Tweed plant.” A. Bennett, Bot. Ex. Club Rep., 1882, p. 78. I 
have only seen a very imperfect specimen of this plant from 
Warwick. 
P. perfoliatus, Linn. Perfoliate Pondweed. 
Native: In rivers, streams, pools, and canals. Locally common. 
June to August. 
I. Oldbury Reservoir ; Coleshill Pool; River Cole, near Colesliill; 
River Blythe, near Barston ; Olton Reservoir; canal near 
Solihull, &c. 
II. In the Stour below Honington, Neiub.; Avon, near Bidford; 
Bearley Canal; Rowington Canal; Sowe Waste and Stoke 
Canals ; pool in Combe Abbey grounds ; old canals near New- 
bold-on-Avon. 
R. crispus, Linn. Curled Pondweed. 
Native : In streams and canals. Local. July to August. 
I. Streams in Sutton Park ; Oldbury Reservoir ; Spring Pool, near 
Kinwalsey ; stream near Blythe Bridge, Solihull; stream near 
Earlswood Reservoir. 
II. Barnes Green, near Coventry, T. K., Herb. Brit. Mus.; old canal, 
between Newbold and Little Harborough ! R. S. R., 1877. 
Radway, Edge Hill; canal near Stratford-on-Avon, abundant; 
stream near Bearley ; Ipsley ; stream at Kingswood ; pool in 
Combe Abbey grounds; stream by Worsley Bridge, Stoneleigh. 
P. densus, Linn. Opposite-leaved Pondweed. 
Native: In ponds. Rare. July, August. 
II. In ponds and ditches on each side the road between Red Hill and 
Stratford-upon-Avon ! Purt., i., 106, abundant in flower in 
1881. Moreton Morrel, H. B., a very small-leaved form ; abun¬ 
dant in pond, Bardon Hill; small pool, Green Lanes, Wilm- 
cote ; narrow-leaved form, canal near Wilmcote ; in abundant 
flower, cattle pond, between Soutliam and Napton-on-the-Hill. 
P, zosterifolius, Schuin. 
Native: In canals. Local. July, August. 
I. Canal, near Atherstone, 1881. Canal near Hockley. 
II. Abundant in the Oxford Canal, near Newbold-on-Avon ! Blox. 
N. B. G.; canal near Rugby ! A. Blox., Herb. Brit. Mus. ; canal, 
Stoke Heath ! 1855, T. K., Herb. Brit. Mus.; Warwick Canal, 
near Warwick and Hatton, H. B. ! canal near Bearley, and 
Stratford-on-Avon; canal, near Holywell and Rowington; 
Napton-on-the-Hill; Sowe Waste Canal, abundant; &c. 
P. obtusifolius, M. and K. Obtuse-leaved Pondweed. 
Native : In canals and pools. Very rare. July, August. 
II. Pit at Kenilworth, II. B., Herb. Brit. Mus.; canal near Stratford- 
on-Avon ; Stoke Heath and Sowe Waste Canals ; cattle pool, 
Banner’s Lane, Tile Hill, in fruit. 
P. mucronatus, Schrad. 
Native : In canals. Very rare. July, August. 
II. Canal, near Warwick, H. B.; canal, near Bearley and Wilmcote ; 
canal, Sowe Waste ; canal, near Newbold-on-Avon ; Napton- 
on-the-Hill Canal. 
