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The Ferns of South Africa. 
CLASSIFICATION OF FERNS AND FERN 
ALLIES. 
Key to the Orders and Genera. 
ORDER I.— FILICES.— FERNS. 
Capsules in groups, on the under surface of the frond ; or on 
differentiated fertile pinnse ; in the latter case not covered by 
an indusium. Capsules one celled, all alike in one species, 
and containing minute uniform spores without filaments. 
Sub-Order I. — Gleicheniace^e. Capsules few in sorus, large, 
composed almost entirely of a broad, elastic, jointed, complete 
ring, which] crosses the top, and opens vertically by the 
separation of two joints of the ring. Fronds dichotomously 
branched. Sori on the back of the frond. Vernation circinate. 
Genus I. — Gleichenia. Characters as above. 
Sub-Order II. — Hymenophyllace^e. Capsules roundish, or 
flattened, surrounded by an obliquely transverse entire ring. 
Capsules enclosed in a cup, and surrounding an elongated re- 
ceptacle, which is terminal on the veins, and marginal on the 
frond. Vernation circinate. 
Genus II. — Hymenophyllum. Involucre a cup of same 
texture as the frond, and placed on its margin, more or less 
compressed, and distinctly two-lipped, or cut into two 
valves. 
Genus III. — Trichomanes. Involucre a deep cup, not 
much compressed, and with an entire mouth, or slightly 
two-lipped when young. 
Sub-Order III. — Polypodiace^e. Capsules many in a sorus, 
small, often stalked, having a jointed elastic band passing up 
