90 
TEE LALY FEEX. 
bears a tuft of incipient fronds, each rolled np sepa¬ 
rately and the mass nestling in a bed of chaff-like 
scales. In May and June they are developed, twenty 
or more being usually produced. In the summer a few 
more generally arise in the centre, the whole dying off 
in the autumn. The form of the fronds is lanceolate, 
more or less broad, the stipes scaly at the base and 
about a third of the length of the frond. The fronds 
are bipinnate, the pinnae always lanceolate, more or 
less drawn out at the point, and always again pinnate, 
though sometimes with the bases of the pinnules con¬ 
nected by a narrow leafy wing, but not so much so as 
to render them merely pinna tifid. The pinnules, how¬ 
ever, are more or less lobed or pinnatifid, the lobes 
being sharply toothed in a varying manner. The 
venation, owing to the delicate texture of the frond, is 
very distinct, consisting in each pinnule of a wavy 
midvein, with alternate and again alternate venules, on 
the anterior side of which, at some distance from the 
margin, is an oblong sorus. In the larger and more 
divided pinnules the venation is more compound, and 
more than one sorus is borne on each primary vein, 
which thus becomes a midvein with branches on a 
smaller scale. The sori are slightly curved, the basal 
very much so, being horse-shoe shaped; the indusia 
of the same form. This horse-shoe shape is made by 
the lateral lines of spore cases crossing the vein and 
then returning, and sometimes the indusia is circular 
all but a small notch, so somewhat resembling the 
fructification of Lastrea. One side of the indusium is 
fixed lengthwise to the side of the vein which forms 
