45^ THE FAMILIES, GEXERA AND SPECIES OF FTERIDOPHYTA. 



Vernation erect (i.e., not circinate); sterile leaf entire 



Group I. 

 Vernation circinate. 



Sterile leaf pinnate Group II. 



Sterile leaf divided into 4 digitate flat segments ... 



Group III. 

 Group I. 



Sporangia in 2 rows on a special spike 



Family I. OPHIOGLOSSACEJE. 



Family I.— PHI GLOSS ACE JE. 



Vernation erect. Sporangia deeply 2-valved, without a ring, 

 forming a dense, 2-ranked spike. — Small herbaceous plants. 

 Leaf-bases usually fleshy and fitting closely together, conceal- 

 ing the stem; the leaf splits into a dorsal and a ventral part, 

 the former being the *' sterile " green leaf, the latter the 

 "fertile ' sporangiferous spike. Only one genus. 



I. Ophioglossum, Linn., Adder's tongue. 



Sporangia sessile, opening by a fissure transverse to the 

 rachis. — Rootstock thickened. Sterile part of leaf usually 

 entire, thick, reticulately veined, the fertile part consisting of 

 a stalked spike. 



Sterile part of leaf ovate, tapering to the base; midrib 



more or less distinct i. vulgafnm. 



Sterile part of leaf cordate at the base, without distinct 



midrib; veins reticulated 2. rcticulatum. 



1. 0. vulgatum, Linn. ATagaliesberg (R. ?) (Burke). 



There is some uncertainty as to the correctness of 

 identification of this specimen. The plant appears 

 never to have been re-collected in the Transvaal. 



2. 0. rcticulatum, Linn. Barberton, Bn. (Thorucroft 



514, j\dc Miss I^eendertz.) 



Group II. 



Sporangia concrete in boat-shaped masses in a double 

 line on the back of the ordinary pinnae, opening" by 



a slit down one side Fam'ily IL MARATTIACEJE. 



Sporangia not in concrete masses; 2-valved. 



Leaves pellucid ; sori marginal ; sporangia with a 

 complete transverse ring; small ferns. 



Family IIL HYMENOPHY LLACE.li. 

 Leaves herbaceous. 



Stems arborescent; sporangia shortly stalked. 

 Leaf bipinnate ; trunk up to 20 ft. high. 



Family IV. CYATHEACEJE. 

 Leaf simplv pinnate, trunk 2-3 ft. high. 



Lomaria in Family V. PO LYPODI ACEJE. 

 Stems not tree-like. 



Sporangia distinctly stalked, numerous, with a 

 vertical incomplete ring, dehiscing trans- 

 verselv Familv V. PO LYPODIACE^. 



