POLYPODIUM VULGARE. 227 
looks like an abortive muss ot fructification. Each 
mass is circular ; depressed at first, but becoming pro- 
minent; without any cover (indusium), and often run- 
ning together when ripe. They are then shining, orange- 
tawny coloured. The spores burst open when moistened. 
The upper part of each frond is usually fertile. 
There are three varieties of this Fern found in the 
British Islands. 
1. Polypodium vulgare Canibrieum, or Common Welsh 
Polypody. It has a broad, somewhat egg-shaped frond, 
with the segments irregularly toothed, and always barren. 
Linnaaus considered it a distinct species. This was first 
known as a British variety in 1686, being then men- 
tioned by Bay in his Historia Plantarum. He says 
that he received it from Sir Hans Sloane, and that it 
was first discovered near Dennis Powis Castle, three 
miles from Cardiff, in Glamorganshire. It has since 
been found at Chepstow, in Monmouthshire, near Dun- 
dry Church, in the vicinity of Bristol, and at Braid 
Hall, near Edinburgh. P. vulgare sinuatum is a very 
slight variation of this. 
2. Polypodium vulgare serratum, or Common toothed 
Polypody. The segments of tins are very regularly, 
and often doubly toothed. It is first mentioned 
as a British variety in 1724 by Dillenius, in 
his edition of Ray's "Synopsis of British Plants." 
He says it was found on the walls of Windsor 
Castle by the Rev. Mr. Manningham. It has been 
found, also, near Bristol, in the Ash ton Manor and 
Leigh Woods. P. vulgare acutum is a very slight 
