FERNS OF THE MALAY- ASIATIC REGION. 
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1. OPHIOGLOSSACErE. 
Rhizome usually underground, small, usually erect, of very slow growth, 
producing one or two leaves annually; fronds small or of moderate size, 
without stipules, straight or folded in vernation (not circinate) ; fertile 
segment very contracted, springing from the ventral face of the sterile 
frond or of its stipe; sporangia large, formed each from a group of 
superficial cells and having a wall several layers of cells thick, without 
any annulus. 
A small family of three genera. These are perhaps the most primitive living 
Pteridophyta. The origin of the sporangium, the vernation, ancl the structure 
of the stomata recall Anthoceros ; and these characters and the occurrence of 
collateral bundles with secondary thickening indicate a close affinity to what must 
have been the ancestors of the flowering plants. 
Veins reticulate 1. Ophioglossum 
Veins free: 
Sterile segment pinnate in plan 2. Botrychium 
Sterile segment trifid, its divisions sparingly pinnate 3. Helminthostachys 
1. OPHIOGLOSSUM Linnaeus. 
Sterile segment entire or sparingly forked, with anastomosing veins ; 
fertile segment likewise simple or rarely forked, fleshy, linear; sporangia 
immersed in the sides of the segment and opening by a slit transverse 
to it. A genus of at most 43 known species, chiefly tropical. 
Fertile and sterile segments separating at or below the base of sterile blade. 
Sterile blade with an ajrparently stout midrib 1. 0. fibrosum 
Without apparently stout midrib. 
Sterile blade linear or lanceolate. 
Segments separating well above ground 2. 0. gramineum 
Common stipe hardly reaching above ground. 
Fertile segment rising from base of sterile 3. 0. japonic-uni 
Sterile segment stalked 4. 0. braunii 
Sterile blade ovate or elliptic. 
Base cuneate or truncate 5. 0. pedunculosum 
Base cordate 6. 0 . reticulatum 
Sterile blade obovate 7. 0. obovatum 
Fertile segment rising from sterile blade. 
Terrestrial 8. 0. intermedium 
Epiphytic 9. 0. pendulum 
Sterile blade practically none 10. 0. simplex 
1. Ophioglossum fibrosum Sebum. 
Rhizome large and globose with numerous fibrous roots; common stipe 
very short; sterile segment 4 to 5 cm long, lanceolate or oblong, acute 
or obtuse, thick and opaque; venation very dense next the costa, giving 
the appearance of a broad midrib; fertile segment 3 to 5 cm long, on a 
stipe of 10 to 12 cm ; sporangia up to 50 on a side. 
Southern India, Sumatra, tropical Africa. 
