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The Essex Naturalist
work out how these ions are accumulated across cell membranes. It is unique in
having a microscopicaly minute cluster of 2-3 dactyls at the tips of its otherwise
single-celled branchlets. A distinctive form, with precociously developed branchlets,
paired, monopodially arranged large-celled dactyls, and whitish bulbils developed on
the nodes of the upper parts of the plant, - that are cross-connected hy branchlets, so
that the whole population forms a gigantic anastomosing network - has been found
by the author twice, in Goldings Hill Upper Pond (Epping Forest). In 1989 it
occurred in quantity, and I suspected that it might be ordinary N. translucens under
the influence of a herbicide. The reappearance of this form in 1997, however, suggests
that it has a genetic basis, and it will be described and illustrated in detail elsewhere.
TQ(51)38 39, 88 18 Snaresbrook, pool, 20 August 1897, Henry Groves.
Two specimens in Natural History Museum
Herbarium (BM). Atlas Specimen No. 2151.
TQ(51)39 39, 91 18 Woodford, 'in gravel pit near the windmill', c.1820.
Edward Forster.
From note penned in margin of copy of Warner's
Plantae Woodfordiensis. Essex Naturalist. 19.
p.229.1918-21.
39, 92 18 Woodford Wells/behind Prospect House', Edward
Forster. From note penned in margin of copy of
Warner's Plantae Woodfordiensis. Essex
Naturalist. 19. p.229.1918-21.
TQ(51)49 ?????? 18 Hainault Forest, c.1830. Ex: Herbarium Forster &
Leighton, three specimens in Natural History
Museum Herbarium (BM). Atlas Specimen No.
2152.
?????? 18 Woodford, June 1887. Henry Groves. Natural
History Museum Herbarium (BM). Atlas Specimen
No. 2155.
?????? 18 Epping Forest, near Loughton, "large tangled masses
in a small deep pond" 13th August 1881. Henry
Groves. Five specimens in Natural History Museum
Herbarium (BM). Atlas Specimen No.2154.
?????? 18 Pond at Loughton, 14 September 1883. Coll: G.
Nicholson, confirmed hy Henry Groves. Natural
History Museum Herbarium (BM). Atlas Specimen
No.2155.
?????? 18 Epping Forest, 26 June 1884. William R.Linton.
Natural History Museum Herbarium (BM). Atlas
Specimen No. 2156.
?????? 18 Pond near Loughton, 23 July 1898. James Groves.
Natural History Museum Herbarium (BM). Atlas
Specimen No.2157.