50 
THE FERN WORLD OF AUSTRALIA. 
XXVII. — Blechnum. Linn. 
Ehizome short and thick, or slightly elongated, and horizontal or 
erect. Fronds pinnate, deeply pinnatifid, or in some species (not 
Australian) bi-pinnate or even simple. Pinnae or segments narrow. 
Sori in a continuous line on each side of the costule, with a mem- 
branous indusium opening from under the costule outwards, the two 
sori often at length confluent, concealing the costule (mid-rib). 
Name from blechnon, the Greek name of a fern. 
B. cartilagineum, Sw. Rhizome short thick, ascending, woody, 
more or less clothed with shining black scales. Fronds one to two 
feet long, the stipes usually scabrous. Segments numerous, three 
to six inches long, almost coriaceous, serrulate, distinctly veined, 
dilated and adnate at the base, the upper ones smaller and confluent, 
the lower ones sometimes distinct. Found along creek-sides and 
borders of scrubs in southern Queensland and N. S. Wales ; also 
several parts of Gippsland, Victoria. 
Var. tropica- Rhizome elongated, ascending or erect, to one 
foot high, and two or three inches thick, by the persistent bases of 
old stipites. Frond as in the species, only larger. A very distinct 
forni found on the damp hill-sides Ranges, Rockingham Bay and 
Trinity Bay. I took this to be identical with PresFs B. nitidum 
from which Mr. Bentham says (Flora Austr. Vol. VI, 739) it differs. 
B. laevigatum, Cav. Rhizome thick and horizontal, very scaly. 
Fronds one to two feet long. Pinnee all distinct, obliquely truncate 
at the base, attached by the costule only, in some fronds all barren, 
one and half to six inches long, half to one inch broad, entire or 
serrulate ; in other fronds all fertile, two to five inches long, two 
hues broad, the sori occupying almost the whole under surface ; in 
other fronds again four to six inches long, four to six lines broad, 
with the sori next the costule as in B. cartilagineum, but not 
adnate to the rhachis. Found so far as known only at Port 
Jackson and the Blue Mountains in N. S. Wales. 
B serrulatum, Rich. Rhizome thick, creeping. Fronds one 
to four feet long. Pinnge distinct, linear or lanceolate, mostly two 
to four inches long and three or four lines broad, obliquely truncate 
at the base but attached by the mid-rib only serrulate, smooth and 
shining, the veins oblique, very numerous and iine, mostly forked. 
Sori close to the mid-rib, indusium soon concealed under them. A 
fern frequently met with in swamps from Port Jackson to Port 
Darwin. 
B. orientalis, Linn. Rhizome erect, stout at the extremity, and 
as well as the stipites, covered with scales. Fronds three to six 
feet long, pinnate. Pinna3 distinct, six inches to near one foot long, 
half to one inch broad near the base, tapering to a long narrow 
point, somewhat cuneate at the base, and attached by the mid-rib 
only, except near the apex of the frond where they are adnate and 
decurrent on the rhachis, the lower pinn^ are also much abbreviated, 
margins entire. Veins simple, rarely forked, very close, parallel, 
horizontal. Sori close to mid-rib, sometimes covering it, indusium 
