THE FERN WORLD OF AUSTRALIA. 
67 
thick texture. Sori large, oval-oblong, inserted in a single row on 
each side of costa half-way between it and the margin. Rather 
plentiful on rocks in the ranges of Queensland, both North and 
South ; and also throughout N. S. Wales. 
P. simplicissimum, F. v. M. Ehizome creeping. Fronds 
lanceolate, acuminate, entire or slightly crenate, four to ten inches 
long, tapering into a short stipes, rathfer thin, glabrous, prominently 
penniveined with intermediate reticulations and free veinlets in the 
areoles. Sori rather large, orbicular, in a single row on each side 
of the costa half-way between it and the margin, the receptacle 
scarcely excavated and obscurely or not at all prominent on the 
upper surface. Rockingham Bay, Queensland. 
P. nigrescens, Blume. Rhizome creeping. Fronds two to 
three feet high on a stipes of one foot, or more, glabrous, deeply 
pinnatifid. Segments lanceolate, acuminate with a narrow point, 
membranous, six inches to one foot long, one to one and a half 
inch broad, confluent at the base in a broad wing to the costa ; 
the main veins very distinct, reticulate between them, with numer- 
ous free veinlets in the areoles. Sori large in the centre of the 
large areoles, distant in a single row on each side of the costule at 
a distance from it, the receptacle deeply excavated and very pro- 
minent on the upper surface. Daintree River, Queensland. 
P. phymatodes, Linn. Rhizome creeping. Fronds two to 
three or more feet high, deeply pinnatifid, smooth and glabrous. 
Segments lanceolate, four to eight inches long, three-quarter to one 
and a half inch broad, confluent at the base into a broadly winged 
costa, the costule of each lobe very prominent, with copious 
reticulations between the primary veins, but all concealed in the 
smooth though not thick texture of the frond. Sori rather large, 
orbicular or oval, distant in about two rows or rarely in a single 
row on each side of the costule at some distance from it," the 
receptacles slightly excavated and prominent on the upper surface. 
There is little or nothing to separate the Australian form of P. 
nigrescens, Bl., from this species. Common near the coast of 
tropical Queensland. 
P. pustulatum, Forst. Rhizome stout, creeping. Fronds 
entire or deeply pinnatifid, three-quarter to one and a half feet 
high, with few segments. Segments oblong-lanceolate, mostly 
acuminate, three to six inches long, four to eight lines broad, 
confluent at the base into a broad-winged costa, of a firm mem- 
branous texture showing on the under side the primary veins, 
with copious intermediate reticulations, and free veinlets in the 
areoles. Sori orbicular, rather large, distant in a single row on 
each side of the costa at a distance from it and often near the 
margin. Receptacles excavated, more or less prominent on the 
upper surface. N. S. Wales, Victoria and Tasmania, rather 
plentiful, creeping over rocks, trunks of trees, &c. A much smafler 
plant but very closely allied to the last. 
P. scandens, Forst. Rhizome slender, creeping over rocks and 
