188 XII. BLECIIXl'M. 
from which proceeds alternate veins ; these extend about 
half-way to the margin, and then each turns at a right 
angle, proceeding along the pinna until it reaches the next 
vein, with which it unites, thus producing a longitudinal 
vein on each side the mid-vein and about equidistant 
between it and the margin. To the inner side of these 
longitudinal veins, which form the receptacles, the spore- 
cases are attached in a continuous series. They are covered 
by an indusium of the same linear continuous form which 
bursts on the inner margin, splitting up at intervals where 
the lateral veins have arisen. The fructification is mature 
in August and September. 
There is a disposition in the fronds of this plant to be- 
come dichotomous, and in one variety for which I am in- 
debted to Mr. J. R. Kinahan, and which I learn is con- 
stant, the apices of the fronds are subdivided in a di-or tri- 
chotomous way, the segments being blunt and curled, so 
that the frond assumes the multifid-crisped character found 
in some forms of Scolopendrium ; this variety is called 
ramosum. It was found near Upper Lough Breagli, 
Wicklow, Ireland. Mr. Wilcke has sent me specimens 
from Blaydonburn and Tanfield Dean, Durham, in the 
former of which the segments are mostly bifid, and in the 
latter coarsely toothed, variations which occur also in the 
common Polypody, but I believe in this as in that case 
inconstant. 
A common species occurring commonly in stony and 
heathy places, and showing itself to be fond of moisture. 
It is generally distributed throughout Europe, and occurs 
in the Canary Islands and at the Cape of Good Hope. 
This plant is of easy culture, and extremely hardy, 
forming a splendid rock plant, and also luxuriating in 
swampy boggy places. It is, moreover, easily obtained, 
and propagates readily by division of its crowns. 
