THE BRYOPHYTES OF CORNWALL
AND THE ISLES OF SCILLY

The vars. of this sp. are only identifiable on the rather infrequent occasions when they bear capsules and have perichaetial bracts that survive with uneroded apices, so all records of non-fertile plants and some of fertile plants are referred only to F. squamosa s. l.

Grows as wefts, 5-20 cm or not infrequently up to 25 cm long. Notes on its habitats in Cornwall are as follows. Attached mainly to rocks (granitic, slaty), but also masonry, concrete, stable gravel, firm hard soil or wood, trailing in shallow water (to 20 cm depth) or hanging where intermittently inundated (up to 20 cm above water level). It grows in soft-water streams and rivers, usually where ± quick-flowing, but is also widespread in winter-flooded zones at edges of Drift, Stithians and Siblyback Reservoirs (mainly in places exposed to wave action). It grows in the open, lightly shaded or sometimes in rather heavily shaded places.

The present species is restricted to soft water, unlike F. antipyretica (see above), and mainly found in well oxygenated quick-flowing water. In middle reaches of R. Tamar F. squamosa grows mainly where permanently submerged, whereas F. antipretica withstands more desiccation and occurs alongside it up to 0.7 m above low summer water levels. In contrast, where F. squamosa occurred with F. antipretica at Drift Reservoir the latter species was much more plentiful and more widespread, occurring in deeper water and more sheltered sites. In a stream near Cape Cornwall it was recorded as extending downstream to near the shore.

Fontinalis squamosa mostly occurs in pure patches but its associates sometimes include Chiloscyphus polyanthos, Fontinalis antipyretica var. antipyretica, Hygrohypnum ochraceum, Platyhypnidium riparioides, Scapania undulata, lichens, less often Leptodictyum riparium, Fissidens fontanus, Platyhypnidium lusitanicum, Thamnobryum alopecurum.