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found at Selworthy, in Somersetshire, by Mrs. Archer Thompson, 
and seems unique. [Plate XXII.— Folio ed. t. X C.] 
14. pterophorum (M.) A form analogous to alatum (18), agreeing in 
the remarkable peculiarity of having the secondary rachides winged, 
and the pinnules consequently united, but differing in being a less 
scaly plant, in having the pinnules less lobed, in the serratures being 
appressed, and in the auricle being almost wanting. It was found in 
Devonshire, near Ottery St. Mary, by Mr. Wollaston. [Plate XX A.] 
15. biserratum (M.). This is one of the large growing forms, and 
is remarkable for its large broad pinnules, which are stalked, inciso- 
serrate, the basal anterior lobe separated by a deeper incision, 
the rest biserrate and in most cases conspicuously aristate. It 
frequently has very long stipites. It seems to be not uncommon, 
since specimens which we refer to this form have been obtained 
from—South Devon, Miss A. Hoseason; Ilfracombe, Rev. J. M. 
Chanter ; Barnstaple, H. F. Dempster, C. Jackson. Somersetshire : 
Nettlecombe, C. Elworthy. Sussex: Littlehampton, E. B. Wollaston. 
Middlesex : Osterley Park, and Lampton Lane near Brentford, S. F. 
Gray. Gloucestershire : Broadwell, H. Buckley. Yorkshire, Whitby, 
W. Willison; Mulgrave Castle, J. Horsfal. Pembrokeshire: 
Castle Malgwyn, near Llechryd, W. Hutchison. Dublin : Glendruid, 
R. Barrington. Jersey, Dr. Alichin, C. Jackson. [Plate XIX C. 
— Folio ed. t. XII D.] f 
Mr. Jackson has found near Barnstaple, Devonshire, three forms 
which we may mention here:—(a) a very large form (magnum), 
the pinnz 64 inches long, pinnules $ of an inch, lobate and 
biserrate ; (b) another large form with shorter pinne than the fore- 
going, but with pinnules equally large, deeply lobate and biserrate, 
the tips of the lobes terminating in a very long seta (setigerum) ; (c) 
. pinnules oblique-oblong obtusely rounded (obtusum), unequally spiny- 
serrate, scarcely auricled or lobed. They come near biserratum. 
16. latipes (M.). This form, related to biserratum (15), has been 
found at Nettlecombe, Somersetshire, by Mr. Elworthy. It is a 
large plant, the pinnules rather more elongated and acute, as well 
as more deeply lobed than in biserratum, but its chief peculiarity 
consists in the lowest pinne being considerably the longest; the base 
of the frond measures upwards of ten inches across. 

