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The Essex Naturalist
TL(52)91 943,182 19 Layer Breton, recently scraped roadside pond, young
plants in shallows, non-fruiting with young
batrachium Ranimculus sp. and Myriophyllum
spicatum. 21 Sept. 1991. Coll: & det: K.J.Adams.
8b Chara globularis var. virgata (Kutz.) R.D. Wood
(=C. delicatula CA. Ag. non Desv. Including C. delicatula var. barbata (Gant.) J.Gr.
& Bullock-Webster.)
This variety of C. globularis used to be regarded as a separate species, C. delicatula,
but apparently intergrades with var. globularis, Moore et al (1986), although Stewart
& Church (1992) still regard it as a good species. Its two secondary rows are
distinctly narrower than the more prominent primary row, and its stipulodes and
spine cells are usually more obviously developed. As the two are said to intergrade
however, some material may be intermediate. Since the relative development of the
cortical rows is used as the main empirically defining character, all specimens will tit
neatly into one variety or the other! It is important to observe the mature axial
segments for this character, however, as in the younger segments the secondary rows
may start off being narrower.
TL(52)69? ??????? 18 Stock, as Chara delicatula var. barbata (Gant.) J.Gr. 6k
Bull.-Webst., near Chelmsford, June 1893, Henry
Groves. Natural History Museum Herbarium
(BM). Atlas Specimen Nos. 672.
TQ(51)88 852,857 18 Leigh-on-Sea, small garden pond, (as C. delicatula
C.A.Ag, non Desv.) July 1981, collected by John
F.Skinner. Det: by K.J.Adams. Pickled material in
Natural History Museum Herbarium (BM) and the
Southend Central Museum Herbarium (STD).
9a Chara aspera Deth. ex Willd. var. aspera
Although similar in its three-rowed cortex structure, it is dioecious, and is a more
delicate plant than C. globularis, with well developed spreading spines and
stipulodes. A distinctive feature is the occurrence of globular, whitish bulbils on the
lower nodes, which it seems largely to rely on for reproduction, rarely being found
in fruit. If found and suspected in the field, one needs to make sure that the lower
segments of the plant are collected, to avoid overlooking the bulbils. Only one old
record for the county.
TL(52)54 53 ,43? 19 Great Chesterford Common, pond, c. 1850, George S.
Gibson. Flora of Essex, p.407.1862.
15a Nitella flexilis (L.) Agardh var. flexilis
This seems to be the most widespread Nitella in the Essex. It has monoecious and
dioecious forms, which are supposed to be slightly different morphologically. The