36
The Essex Naturalist
tracked down to the BM herbarium and confirmed. This find is an example of
the sporadic and impermanent nature of many bryophyte species. Like the seeds
of orchids, bryophyte spores travel many hundreds, even thousands of miles in
air currents, and can take hold anywhere, where conditions are conducive.
New records resulting from further examination of Eric Saunders' Herbarium
include: Aloina brevirostris vcl9 and Bryum donianum vcl8. His vcl9 voucher of
Seligeria paucifolia (BBSUK) however, has since been shown to be S. calcarea.
Three other species have also been redetermined. The long since extinct
Racomitrium canescens sensu lato, recorded by Dr E Varenne in 1860 on Tiptree
Heath (PEM) has been critically redetermined as R. ericoides (Brid.) Brid.
Varenne's specimen of the highly SO, sensitive Zygodon conoideus from
Kelvedon, has been relocated in the PEM herbarium, and is presumably the
source of the old vc19 record. Tim Pyner has recently found a new colony of Z.
conoideus for vc19 at West Bergholt. A specimen collected on Epping Forest
"corner of Block's Road, Epping Forest" ] L English, 1912 (PEM), cannot be
submitted as a voucher tor vc18 however, until the mysterious "Block's Road"
can be geographically located.
The (in Essex) scarce liverwort Lophozia ventricosa var. ventricosa has been
resubmitted recently for vcl8, following confirmation of the oil-body character
in living material, and the alien moss originally recorded for vc19 as Tortula
stanfordensis, subsequently split off from the former species as Tortula brevis, has
recently been shown to be synonymous with the Australasian Hennediella
macrophylla (Blockeel 1990).
Several species of alien bryophyte have invaded Essex in recent decades.
Orthodontium lineare had colonised Essex by the time of the 1974 Bryophyte
Flora. Campylopus introflexus however, was only just beginning to expand. Today
it is a conspicuous and in many places dominant moss of heathland tracks and
the floor of dry acid woodland. The hard-wearing mossy tracks at the
Fingringhoe Wick N.R. are almost entirely composed of this species.
Other species, such as Ptilidium pulcherrimum, which do not produce
sporophytes in Essex, and seem to be impermanent, are believed to be
replenished by spores crossing the north sea from the continent. Finally, it is
often difficult in a county without much natural hard rock, to know what to do
about species that are introduced from outside the county on garden rocks and
building materials. Tortella tortuosa, for example, has been found on limestone
blocks in Central Park, Chelmsford (vc19), and has persisted and increased on
carboniferous limestone blocks in a garden at Loughton (vc18) for over 20 years.
The BBS recorders generally frown on such records. Material on gravestones,
however, is generally accepted, although it may sometimes also have originated
as an introduction.
All the records listed here have been submitted to either the BBS hepatic or
moss recorder for confirmation and have been lodged as voucher specimens in