







THE BRITISH FERNS. 
10. serratum (Willd.). The lobes in the typical state of this 
form are sharply and deeply serrate or even biserrate along their 
margins, and the apices are acute. The fronds are nearly of the 
usual outline, and with a tendency in the sori to become oblong. It 
varies, however, with the fronds rather broader, and the teeth 
somewhat rounded and sometimes partially enlarged into lobes, 
connecting this form with the variety crenatum. It has been found 
in—Kent: Sidcup, G. B. Wollaston ; Tunbridge Wells, Mrs. Delves. 
Surrey: Godalming, H. Bull; Woking; Mayford; Shere. Sussex: 
Balcombe, S. O. Gray; Hastings, Dr. Allchin. Somerset: Cheddar; 
Nettlecombe, C. Elworthy. Devon: Moreton Hampstead, Rev. 
J. M. Chanter. Cornwall: Saltash, Rev. C. Trelawny. Mon- 
mouth: Chepstow, S. F. Gray. Hereford: Whitchurch; Mordi- 
ford. Warwickshire: Moseley near Birmingham. Gloucestershire. 
Oxfordshire: Cornwell, H. Buckley. Worcestershire: Malvern. 
Yorkshire: Byland Abbey, C. Monkman. Pembrokeshire: Castle 
Malgwyn, W. Hutchison. Denbighshire: Ruthin, 7. Pritchard. 
Kirkeudbrightshire. Stirling, Mrs. Macleod. Galway. Clare: Bal- 
linahinch. Waterford: Blackwater. Guernsey, C. Jackson. [Plate 
III B.—Folio ed. t. II B.] 
A finely serrulated biserrate plant (biserratum) referrible to this 
form of the species, occurs at Eltham, G. B. Wollaston. 
Broad or ovate-fronded Series. 
ll. denticulatum (M.). This form has fronds less coriaceous than 
usual, of a broad oblong outline, abrupt from the uppermost lobes 
not diminishing but terminating suddenly below the caudate apex; 
all the lobes are ascending, and notched with rather distant small 
sharp teeth. It has been found near Hereford, Dr. Alichin; and 
on Rochester Castle, C. A. Chanter. [Plate III D.] 
An analogous but still broader form, having an ovate outline, 
found in Portugal, the Canary Islands, &e., is called canariense, 
and fronds resembling this have been gathered in Ireland, e. g. 
Lough Gill, Sligo, and Killarney, R. Barrington. Another similar 
form is the P. virginianum of North America. 
12. crenatum (Woll.). This is a large growing form, approaching 
semilacerum by its broad or ovate fronds, and lobed segments; but 

