i37 
NAIADACE/E. 
Triglochin (L.). Arrowgrass. 
T. palustre ( L .). Fig. 653. Marsh Arrowgrass. Native. P. 
VII, VIII. 
Marshy places. Frequent. 
L. Formby to Haskayne, Barton and Halsall. 
C. Burton, Leasowe, Mollington. Wallasey Marsh ; Raby * 
S. U. Canal banks ; Backford. 
T. maritimum (L.). Fig. 65$ Seaside Arrowgrass. Native. P. 
VII, VIII. 
Salt marshes. Frequent. 
L. Mouth of the R. Alt ; Dungeon. 
C. Leasowe; West Kirby; Burton Marshes; Bromborough 
Pool. 
Potomogeton (L.). Pondweed. 
P. natans (L.). Fig. 658. Floating Pondweed. Native. P. 
VI, VII. 
Ponds and ditches. Common. 
P. polygonifolius (Pour.). Oblong-leaved Pondweed. Native. P. 
VII. 
Ponds and ditches. Rare. 
L. Canal at Litherland (H.). Moss Pit, Aintree (f.m.w.). 
Pond in quarry N.W. of R. C. Chapel, Little Crosby (j.h.l.). 
C. Oxton Heath (f.m.w. ; h.s.f.). Dykes in the Langfields, 
West Kirby (f.m.w.). 
P. rufescens ( Schrad .). Reddish Pondweed. Native. P. VII. 
Streams and ditches. Occasional. 
L. Altcar Marsh; Formby Marsh (D). Near Warrington 
(t.g.). In North Moss Lane, Formby (f.m.w.). 
C. Pond between Ledsham Station and Hailwood Farm; 
near W. end of Capenhurst ; E. of Hargreave Hall ; Pond 
between Capenhurst and Ledsham ; Pond between Ledsham 
and Willaston (r.b.). 
P. heterophyllus ( Schreb .). Fig. 656. Various-leaved Pondweed. 
Native. P. VI, VII. 
Ponds and ditches. Rare. 
L. Marsh and ditches N. of Crosby (D.). Near Birkdale 
(h.s.f.; f.p.m.). Shallow pool among the sandhills between 
Formby and Freshfield (e.d.). 
C. Bidston Marsh (H.). Pond between Thurstaston and 
Dawpool (r.b.). 
