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The Essex Naturalist
ditto, new form found again with grapnel, growing
with Ceratophyllum demersum, in deep water behind
the island. 20 April 1997. Coll: & det: K.J.Adams.
TQ(51)69 610,906 18 Childerditch, abundant, free of epiphytes, sterile,
eastern margin of Childerditch Upper Pond. Other
aquatics present: Potamogeton natans and Callitriche
stagnalis. 12 September. 1987. Coll: 6k det: K.J.Adams
(et LNHS).
ditto, abundant in deep water, retrieved by grapnel
c.3m south of north shore, Childerditch Upper Pond.
29 June 1991. Coll: & det: K.J.Adams et EFC.
TL(52)81 ??????? 19 Tiptree, clay pits, as Chara translucens, 1858
Dr.Ezekiel G.Varenne. Flora of Essex, p.406. 1862.
18a Nitella mucronata (A.Braun) Miquel var. mucronata
Although an Irish Red Data Book species, it appears as though it may be widespread
and locally abundant in Essex. It is difficult to tell whether its a new arrival that is
increasing, possibly because it can now tolerate the current levels of much cleaner,
recycled sewage water in our rivers and canals, or has not been recorded before,
because noone has looked for it along the centre of our canals and rivers. Our
material all conforms to the var. mucronata with two-celled datyls, the apical cells
being minute and onion shaped, - although the form that is obviously increasing
elsewhere in Britain is predominantly the var. gracillima, a more slender, more
umbellate planr, with tapering 2-3 celled dactyls. This latter variety should be looked
out for in Essex, as it has been found in Cambs. and Norfolk.
TQ(52)49 414,980 18 Small plastic-lined pool by Epping Forest
Conservation Centre, High Beach, 4 March 1995.
Coll: & det: K.J.Adams.
TL(52)41/42497,195 19 East side of R. Stort, Gt. Hallingbury, Sept. 1987.
Coll: Shirley & Charles Watson, det: K.J. Adams.
49 ,19 19 All the way down the R. Stort Navigation from
Bishop's Stortford to Twyford's Lock, in deep water
with Chaetomorpha.
4 Oct. 1987. Coll: & det: K.J.Adams et LNHS/EFC.
49 ,18 19 R. Stort, just north of Wallbury Dells, N. Essex.
22 Feb. 1992. Coll: 6k det: Jeremy Ison.
495,200 19 R. Stort, all the way down stream between these
to 495,192 limits, 22 June 1992. Coll: 6k det: Jeremy Ison.
TL(52)70 742,079 18/19 Detached material on weir, sterile, Chelmer 6k
Blackwater Canal, nr. Cuton Lock, Springfield. 9
Feb. 1991. Coll: 6k det: Tim Pyner.
750,081 18/19 Boreham, in Chelmer-Blackwater canal, sterile, ni.
Stonehams Lock. 7 August 1990. Tim Pyner.