*1: Near Flushing,
Falmouth, 1842, EAW
(TRU) (Paton 1969a:
744).
*2: Penventinue, Fowey,
1904, RWS (TRU) (Paton 1969a:
744).
The morphology varies considerably with submerged
plants and small plants from exposed banks often lacking the
usual dendroid habit.
Notes on habitats in C&S are as follows. Often
abundant and large on rocks not far above water-level of
streams and rivers, mainly but not exclusively in sheltered,
shady sites such as in woodland, sometimes in heavy shade (but
also in open above N.-facing sea-cliff). Grows on vertical,
inclined and horizontal surfaces, and on substrates that
include granite, gabbro, serpentinite, slates, concrete and
wall-mortar. Usually grows largest where there is spray, e.g.
from a waterfall or sluice, and grows on surfaces within the
flood-zone at some sites. Also occurs away from water on rocks
and masonry, mainly in sheltered, humid places in woodland or
at least under trees, including old quarries, rocks and steep
soil on shaded Cornish hedges, laneside banks and old walls,
on a wall top and in sheltered churchyards. Infrequently found
on horizontal soil, but often on sloping, moist, shaded soil
on stream banks and other sheltered banks such as on lanesides
and those around the northern side of some churches (where it
may extend locally onto flat soil among lawn grasses). Single
records from low on granitic sea-cliff in crack with trickling
water (more often high up on slopes above cliffs), and on
horizontal concrete at reservoir edge under Grey
Willows.
Commonly on bark of trees and exposed roots low in
flood-zones of rivers. Also extends onto tree bases and low
branches in some humid sites e.g. in woodlands, the few
records including Alder, Ash, Beech, Sycamore, Elder and Grey
Willow. Also once in quantity on side of old, fallen, decaying
elm trunk near stream.
Frequent associates include Brachythecium
rutabulum, Conocephalum
conicum,
Oxyrrhynchium hians, Kindbergia
praelonga,
Lophocolea bidentata, Plagiomnium
undulatum,
Platyhypnidium riparioides; also many vascular plants,
e.g. Hedera
hibernica, Primula
vulgaris, ferns; scarcer associates include: Cratoneuron
filicinum,
Dumortiera hirsuta,
Fontinalis squamosa, Homalia
trichomanoides,
Pellia endiviifolia; epiphytes recorded on Thamnobryum alopecurum
once included Lejeunea
patens.
Capsules mainly occasional and typically few in
number, but apparently frequent and numerous in some
sheltered, humid sites; capsules immature 1, 10-12; dehiscing
1, [5], 11, 12; dehisced 1, 3, 4, 10. Literature states ripe
in 'autumn', but winter would seem more
appropriate.
