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The Ferns of South Africa. 
DESCRIPTIONS OF THE SPECIES. 
(Technical terms and contractions for the names of botanists or books are 
explained in the Glossary at the end.) 
ORDER I.—FILICES.— FERNS. 
Sub-Order I. — Gleicheniace^e. 
Genus I. — Gleichenia. Smith. 
Rhizomes widely creeping, slender. Fronds distant, dichotomous, 
or repeatedly dichotomous, the ultimate branches with pinnately 
arranged pinnules. Sori on the back of the pinnules, composed 
of few capsules, without indusium. Capsules sessile, with a very 
wide, complete ring, and opening vertically by the separation of 
two joints of the ring. 
These beautiful ferns are distinguished at a glance by the 
dichotomous branching of the fronds, which occurs in no other 
South African genus. In the centre of each fork is a bud, and 
sometimes the one at the first fork develops late in the season into 
a strong branch, also dichotomously branching, thus giving the 
frond a somewhat pinnate appearance. The Gleichenias are quite 
distinct in appearance, and equal in beauty most ferns, but, unfor- 
tunately, do not readily adapt themselves to cultivation, and are 
seldom seen away from their native habitats. They are distributed 
through most of the Southern Hemisphere. 
Key to the species : — 
§ Pinnules nearly as broad as long. Sori at the apex of a veinlet. 
(Engleichenia.) 
1. G. polypodioides. 
§§ Pinnules much longer than broad. Sori medial on a veinlet. 
(Mertensia.) 
2. G. umbraculifera, pinnules occurring on all the dichotomous 
branches. 
3. G. dichotoma, Pinnules on the terminal pinnae, but absent from the 
lower dichotomous branches, where each fork is subtended by a pair 
of small pinnated pinnae. 
