Descriptions of the Species. 
I2 5 
Genus XVII. — Blechnum. Linn. 
Sori parallel with the mid-rib and the margin ; placed about 
half-way between them ; continuous, and with indusium opening 
inward. 
A small genus of ferns, very similar in habit to Lomaria, but 
with the sori not marginal. B. australe is, however, very variable, 
and often answers to Lomaria, while in both our species the sori 
are frequently interrupted, as in Doodia. Most of the species are 
tropical. 
Synopsis of the species : — 
64. B. australe. Rachis and frond destitute of glandular hairs. 
65. B. remotum. Rachis and frond densely covered with very short, 
glandular hairs. 
64. Blechnum australe. Linn. 
Plate LIX. a. Barren frond, nat. size. b. Fertile frond, nat. size. c. Pinna 
of toothed form. 
Crown procumbent, paleaceous, producing many simply 
pinnate, lanceolate, coriaceous fronds, and a few slender, sub- 
terranean rhizomes, which produce, at a distance of six to twenty- 
four inches, a new crown, but with few or no fronds between. 
Fronds six to twenty-four inches long, one to two inches broad at 
the middle, and tapering very gradually to the point, and also to 
the base, where the pinnae are distant, and very much reduced; the 
lowest often within two inches of the crown, but sometimes leaving 
a bare stipe of six to eight inches, which is paleaceous below, but 
glabrous above, and like the glabrous rachis, slightly channelled 
in front. Pinnae of barren frond very various, generally one-half 
to one and a half inches long, three to four lines broad, oblong or 
widely lanceolate, often falcate, tapering to a sharp point, the 
upper adnate by almost their whole bases ; those in the middle of 
the frond sessile, but rounded to a narrow connection ; those 
below auricled on one or both sides, and connected by the mid- 
rib only ; while the reduced lower ones are triangular, and often 
three-pointed. Fertile pinnae one and a-half to three lines broad, 
