228 
ST. ALBANS AND ITS NEIGHBOURHOOD. 
2. Filices, Musci, Hepatic^:, and Algje. 
Little can be said respecting tlie oecology of the Cryptogamia 
of onr area, for with the exception of the Filices and Algae 
practically no work has been done, from this standpoint, on 
the various groups. We are greatly in need of workers to 
undertake this aspect of Cryptogamic research. Eecords of 
the rarer forms alone are comparatively useless ; the need is 
for complete lists from as many localities as possible, with 
data as to the soil and environmental conditions of each species 
together with details of association both with regard to the other 
Cryptogams and also to the Phanerogamic Flora. 
Felices. —The ferns of the district, though never common 
(with the exception of the bracken, which is increasing rapidly), 
are becoming rarer every year, no doubt due in the main to 
the lowering of the water-level and to the rapid increase of 
population. The most frequent of the ferns are Aspidium 
filix-mas, A. angular e, Poly podium vulgar e, and Asplenium 
adiantum-nigrum. Blechnum spicant, Asplenium trichomanes, 
A. ruta-muraria, and Ophioglossum vulgatum are now distinctly 
rare, and Ceteracli officinarum , which formerly occurred at 
Harpenden, is extinct. 
Musci.—About eighty species of mosses have been recorded 
from the district, but the paucity of workers in this field has 
doubtless left many lacunae. 
The Sphagnaceae are, like their habitat, rare in our area. 
Sphagnum subsecundum is found at Colney Heath and at 
Bricket Wood, in which latter locality the two varieties, var. 
contortum and var. obesum, and also S. intermedium occur. 
Other water-loving mosses found in the district are Philonotis 
fontana, Webbera carnea, W. albicans, and Fissidens adiantoides. 
Besides supplying our wettest forms, Bricket Wood and Colney 
Heath are the only localities for Leucobryum glaucum. 
Quite a moss flora is to be found on the old walls of 
Verulam, including, besides the more common species, Barbula 
unguiculata, B. revoluta, Fncalypta vulgaris, Bartramia pomi- 
formis, Furhynchium crassinervum, and Bhynchostegium confertum. 
The walls at Grorhambury also yield some interesting species 
such as Barbula vinealis and Furhynchium pumilum ; here also 
on the banks and fields may be found Pottia starkeana, 
Bidymodon rubellus, and Hypnum chrysophyllum. Most of the 
records for the district are to be found in Mr. A. E. Gribbs’ 
paper in our ‘ Transactions ’ (Yol. Ill, pp. 67-81). 
Hepatigze. —The number of Hepatic® recorded is small. The 
complete list is given in the hope that it will stimulate new 
workers to add to their number. Marchantia polymorpha, 
Asterella hemispherica, Frullania dilatata, F. tamarisci, Badula, 
complanata, Porella platyphylla, Odontoschisma sphagni, 
Cephalozoa zyssacea, C. bicuspidata, Lophocolea bidentata, 
L. heterophylla, Chiloscyphus polyanthus, Scapania nemorosa, 
