Ceratopteris.] OLVI. FILIOES. 1987 



variously shaped segments, flat and of a soft half succulent texture. Spore-cases 

 with a broad nearly complete ring.— Beddome, Ferns S. Ind. t. 75 ; Bail. 

 Litho. Ferns, Ql. 12 ; Parkeria pteridioides, Hook. Exot. Fi. t. 147 ; Hbok. and 

 Grev. lo. Filic. t. 97. 



Hab.: Gulf of Carpentaria, Landiborough; Cape York, Daemel; Cape York Peninsula, iV. 

 Taylor ; Bookingham Bay, DMaehy ; Eookingham. and neighbouring districts, Bowman, 

 O'Skanesy ; Moreton Bay, F. v. Mueller. 



9. PLATYZOMA, R. Br. 



(Prom platys, broad ; zoma, a band ; the ring of the sporangia broad.) 



Fronds tufted on a horizontal rhizome, pinnate, the pinnules small and 

 numerous along a simple rhachis. Sori of 2 to 4 spore-cases, terminating simple 

 veinlets proceeding from the midrib, the soriferous end free and incurved between 

 the frond and an inner membrane. Mature spore-cases globular, very deciduous, 

 bursting irregularly, the inner membrane of the pinnule irregularly torn and 

 disappearing. 



ihe genus is limited to the single speoies endemic in Australia, the great difference in 

 fructification as well as in habit preclude its union with Gleichenia. 



1. P. microphyllum (leaf small), R. Br. Prod. 160 ; Benth. Fl. Austr. 

 vii. 696. Braid Fern. Rhizome short, thick, densely covered with long brown 

 setaceous scales. Fronds 6in. to above 1ft. high, the rhachis smooth and shining. 

 Pinnse exceedingly numerous, scarcely above 1 line long and broad, the revolute 

 margins almost closed over the midrib so as to give them a globular or ovoid 

 buUate form, glabrous outside, powdery inside especially on the midrib. 

 Soriferous veins 2 or 3 on each side of the midrib. — Hook, and Bak. Syn. 

 Filic. 11, t. 1, f. 1 ; Guillem. lo. PI. Austral, t. 13 ; Gleichenia plcbtyzoma, 

 F. v. M. Fragm. v. 114 ; Bail. Litho. Ferns QL 13. 



Hab.; Gulf of Carpentaria, R. Brown, Gulliver; Facing Island, R. Brown, W. Hill; York 

 Peninsula, Taylor; Rockinghain Bay, Dallachy ; Downs of the interior, Mitchell, WoolU, 

 Birch, Bowman and others. 



It is not easy in dried specimens to find the perfect sori in situ, for when ripe they are 

 generally seen loose in the pinnule, and the inner membrane which confined them broken up or 

 withered away. 



10. GLEICHENIA, Sm. 



(After Baron P. von Gleichen.) 



Fronds from a creeping rhizome erect or scrambling, the main rhachis 

 diohotomous, with numerous entire or pinnatifid pinnules, distichous along the 

 ultimate branches and often also below the last forks. Sori without indusium, 

 of few (2 to 12) spore-cases attached to one branch of forked veinlets, either 

 superficial or slightly embedded in the substance of the frond. Spore-cases 

 surrounded by a transverse ring and opening vertically in 2 valves. 



The genua is spread over the tropical and subtropical regions of the New and the Old World 

 extending into cooler regions in the southern hemisphere. 

 Pinnules divided to the midrib into numerous small segments, 'each with 



a single sorus. 

 Segments flat or with recurved margins, not buUate. Spore-cases usually 



3 or 4, near the upper inner angle . . 1. G. circinata. 



Segments buUate, the recurved margins almost closed over to the rhachis. 



Spore-cases usually 2, in a cavity more than half the breadth of the 



segment 2. G. dicarpa. 



Pinnules entire or scarcely serrulate. Veinlets pinnate along the midrib, 



forked, each with a sorua on bile branch. 

 Pinnules green on both sides, continued on the branches of the rhachis 



below the last fork. Sori of 3 or 4 spore-cases 3. (?. /labellata. 



Pinnules linear-lanceolate, sometimes glaucous underneath. Spore-oases 



about 4 . • ■ . 4. ff. Aagellaris, 



Pinnules glaucous underneath, only on the last branches of the rhachis 



abSve tha last fork. Sori of 8 or more spore-caeee 3. (?. diehotoma. 



