352 
THE FERN WORLD 
stalks which support them; sometimes fail-shaped and 
similarly attached by their narrow ends, and not unfre- 
quently diamond-shaped. Occasionally the pinnules are 
again deeply cleft, or divided, thus giving a tripinnate 
appearance to the frond. The length and number of 
divisions of the pinnae decrease towards the apex of the 
frond, until they are reduced to single club-shaped lobes, 
which are slightly and irregularly toothed or serrated — the 
extreme point of the frond consisting of a single pear- 
shaped, diamond-shaped, or roundish lobe. The venation is 
somewhat indistinct, owing to the almost opaque character 
of the leafy substance of the frond. A number of veins, 
however, enter the lobes from their bases, and proceed 
thence towards the upper and wider ends, becoming branched 
as they proceed, a branch or venule ordinarily passing into 
each of the marginal serratures. The sori are borne in lines 
along this system of veins, covered when young by their 
longitudinal indusia, but becoming free when the develop- 
ment of the fructification has made some progress and 
burst its envelopes, and finally merging, or becoming con- 
fluent, and then densely covering the under surface of the 
little pinnules. When the fructification is quite perfect, the 
little plant presents a curious and interesting appearance — 
the upper sides of its fronds a dark shining green, their 
under side dark rich brown from the dense aggregation of 
uncovered seed cases. The fronds are very hardy and per- 
sistently evergreen, withstanding the frosts of winter, and 
endure until the fronds of the succeeding spring have been 
produced. There are upwards of fifteen variations from the 
normal form of this species. 
Distribution. — On the continent of Europe the Kue- 
leaved Spleemvort has a very wide distribution, ranging 
through Belgium, Bohemia, Corsica, the Crimea, Croatia, 
Dalmatia, France, Germany, Greece, Holland, Hungary, 
