THE COMMON POLYPODY IN ESSEX. Paes) 
- interesting records : seven species are now recorded from Epping Forest for 
the first time, viz. :— 
Lepiota clypeolaria (Bull.) Fr. 
Tricholoma cinerascens (Bull.) Quel. 
Collvbia tesquovrum Fr. 
Hebeloma glutinosum (Lindgr.) Fr. 
Psalliota xanthoderma Genev. 
Hvpholoma leucotephrum B. and Br. 
Peniophora sanguinea (Fr.) Bres. 
THE COMMON POLYPODY IN ESSEX: 
WHY IS 1T DECREASING ? 
BYeMILLER CHRISTY, F.L.S. 
VERYONE familiar with the flora of Essex is aware that 
the true ferns (Filices) form an extremely small proportion. 
It is not so much that the number of species indigenous to the 
_county is particularly limited ; for such is not the case. Gibson. 
enumerates, indeed, no fewer than twenty species as occurring.t 
The point is, rather, that the number of individual plants repre- 
senting those species is, in most cases, extremely small. Anyone 
able to compare the fern-flora of Essex with that of Devonshire 
or any other western county realizes at once the great poverty 
of our county in this respect. In Essex, we have only one single 
species which can be described as really abundant—the Common 
Bracken (Pteris aquilina). The Polypody (Polypodiwm vulgare), 
is, however, quite common, and the little Adder’s-Tongue 
(Ophioglossum vulgatum) is fairly so. Devonshire, on the other 
hand, has at least a dozen species, all of which are more or less 
abundant. 
That the fern-flora of Essex must always have been very 
meagre, not only comparatively, but actually, is certain ; for 
Essex, as the driest county in England, lacks that humidity of 
climate, due to heavy rainfall, which 1s so necessary for luxuriant 
fern-growth. Our mean average rainfall is about 23 inches 
annually : that of Devonshire, about 41 inches, or nearly twice 
as much. There, the climate is so moist that fern-spores propa- 
gate readily every year ; whereas, in Essex (as Mr. Shenstone 
1 Flora of Essex, pp. 394-404 (1862). 
