THE SEA SPLEENWORT. 99 
two fronds appear to grow side by side from one point. The pinne 
are, moreover, remarkable in their form and appearance, and give 
the plant a very distinet aspect; the lower ones are bluntly three- 
cornered and nearly equal-sided, while upwards they are narrower 
so as to become more ovate, and they are also more oblique; they 
have usually a large rounded anterior auricle, and frequently the 
posterior base also bears a large rounded lobe; these pinnse are some- 
what undulated, coarsely erenate-lobate, with the lobes indistinctly 
crenate-toothed. The sori are abundant, and prominent. This rare 
and thoroughly constant form, was found in 1850 by Mr. Wollaston, 
in Dorsetshire. [Plate LXXIII bis, B. ] 
6. incisum (M.). This is a small and elegant form, remarkable 
for the deep and uneven incisions in the margin of its pinne. The 
same form is figured by Dr. Deakin,* but no habitat or description 
isgiven; the specimen however is represented about seven inches 
in length, exclusive of the stipes, and having about sixteen pairs of 
distant pinne. The examples we have seen are much smaller 
than this. The pinn® are short, scarcely more than half an inch 
long, very obliquely semi-ovate, truncate and auricled at the anterior 
base, and. with about three deep incisions along the anterior margin, 
blunt ended, the posterior side narrow, with a few deep lobes, and 
sloping off in a wedge-shaped manner at the base. A few large sori 
are produced chiefly at the anterior edge of the lobes, which lobes 
are all obscurely toothed. We have seen specimens from Carnar- 
vonshire: Great Orme's Head, A. Stowe, communicated by Mr. C. 
Griffith; and Denbighshire: near Llangollen, communicated by 
the Rev. T. Rooper. [Plate LXXIV A.] 
7. parallelum (M.). A large form, growing about three feet long, 
the pinne somewhat distant, but occupying two feet of that length. 
The pinne are from two to two and a half inches long, and less 
than three-eighths wide, nearly parallel-sided, the base wedge-shaped, 
the margin coarsely but not deeply crenate-serrate, and the apex 
bluntish. It was found in Guernsey by M. Boistel. A somewhat 
similar plant, but having a ramose tendency in the rachis, has been 
found in Cornwall, by Mr. Atkins. [Plate LXXIV C.] 
* Deakin, Florigraph. Brit, iv. 70, fig. œ. 

