84 
questionably P. alpinus var. Palmeri Druee and not a hybrid, 
as suggested in L. C. 1925. The late Arth. Bennett admitted 
this later, in litt. 1928. — W. H. Pearsall. 
Potamogeton heterophyllus Schreb. In the Basingstoke 
Canal, near Byfleet, Surrey, Sept. 14, 1930. In shallow water 
close to the banks. Fruiting specimens scarce and poor. — 
E. C. Wallace. These are P. gramineus L. var. lacustris 
Fries. The plants have been growing in relatively shallow 
water and therefore do not show the characteristic dense 
mass of vegetation at the base of stems growing in deeper 
water. They possess, however, excellent examples of the 
floating-leaves of this species. — W. H. Pearsall. 
Potamogeton [ varians Fryer]. Witcham Medlands, Cambs., 
Sept. 9, 1909. — E. W. Hunnybun. Comm., Nat. Mus Wales. 
The sheet submitted is a slender short-leaved form of P. 
gramineus L. included under var. lacustris Fries. It exhibits 
no character not included among those of that species and, 
moreover, possesses all the essential features of P. gramineus, 
all submerged leaves sessile, linear-lanceolate with narrowly 
tapered lanceolate bases neither rounded nor cordate, 
serrulate margins, sharply pointed apex and normal venation. 
In addition, it shows the well-formed typical fruits of that 
species. The name varians Fryer is invalid as it represents 
more than one form. The great majority of plants so labelled 
are undoubtedly forms of P. gramineus, and the late Mr. A. 
Bennett, recognising this, omitted the name from the latest 
(1925) L. C. list. There are, however, a few sheets still in 
existence, bearing the label P. varians Fryer, which are 
hybrids of P. gramineus and some other species. — W. H. 
Pearsall. 
Potamogeton gwfoliatus Linn. Kennet and Avon Canal, 
near Great Bedwyn, Wilts., Aug. 24, 1930. — E. C. Wallace. 
Tvpical examples of P. perfoliatus var. ovatifolius Wallr. — 
W. H. Pearsall. 
Potamogeton interruptus Kit. Brackish pool, near Cuckmere 
Haven, E. Sussex, Aug. 10, 1930. [Pv,ef. B 2]. — J. E. Lousley. 
The correct citation for these line examples is P. pectinatus 
L. var. diffusus Hagstr. f. interruptus (Kit.) Asch. This plant 
was originally described as a species by P. Kitaibel in Schultes, 
dsterr. FI. 1814, 328. Babington [Man. ed. 3, 1851, 343) still 
regarded it as such and named it P. flabellatus. In 1864, 
