The Essex Naturalist
141
TL(52)80 810,086 18/19 Chelmer & Blackwater Navigation, just east of Hoe
Mill bridge, Ulting, retrieved by grapnel from the
central channel on Vcl8-19 boundary, with
Potamogeton trichodes. 12 Aug. 1990. Coll: & det:
K.J.Adams et EFC.
19 Nitella gracilis (Smith) Agardh
Only a single old record of this very rare Red Data Book species for Essex. It closely
resembles the var. gracillima of Nitella mucronata, with its tapering 3-celled dactyls,
but it is a smaller, more delicate plant with axes less than 0.5mm diameter, and has a
yellowish to brownish-green, as opposed to dark green colour.
TL(52)84 ??????? 19 Near Sudbury, on Essex side of Stour, as Chara gracilis,
c.1850. Dr Ezekiel G.Varenne. Flora of Essex p.406.
1862.
23 Tolypella intricata (Trent. ex Roth) Leonh.
The two main groups of Tolypella are separated by the shape of the end cells of the
branchlets. In T. intricata ( and T. prolifera) the end cells are conical and acute,
whereas those of the T. nidifica agg. are blunt, the last few cells resembling a string of
sausages. T. intricata differs from T. prolifera in being a more slender plant, having
once divided sterile branchlets with 2-3 end rays. It is a sporadic plant that seldom
appears in the same place twice, and often develops over winter, producing ripe
oospores by Easter and then disintegrating.
TL(52)63 ??????? 19 Ditch nr. Hempstead Wood, as Chara polysperma
A.Br., George S. Gibson. Flora of Essex p.406.
1862.
TL(52)81 ??????? 19 Kelvedon, 10 June 1877. Coll: Dr Ezekiel G.Varenne.
ex herb: James Groves. B.E.C. Report Vol.1, p. 12.
1877-78. Also two specimens Natural History
Museum Herbarium (BM). Atlas Specimen No.
2327.
TL(52)83 ??????? 19 Twinstead. June 1918. Coll: George C. Druce, redet:
James Groves. Not refound in 1919. Cambridge
Herbarium (CGE). Originally misidentified by
Druce as T. glomerata. Botanical Exchange Club
Rep. for 1918. 5. p.411-412 and p.534.
25b Tolypella nidifica var. glomerata (Desv.) R.D. Wood
This is the commonest Tolypella taxon in Britain. Like T. intricata it can germinate
in the autumn and overwinter, although fruiting somewhat later in June/July. It can
also, however, be a summer annual, germinating in May and fruiting by July (Moore,
1986). We do not have enough data to tell whether it persists in the same place from