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THE FERNS OF SOUTH AFRICA 
Genus 58. Selaginella. Capsules of two kinds arranged 
in the axils of bracts in a terminal spike, the smaller 
kind toward the apex and the larger kind toward 
the base of the spike. Leaves dimorphous. 
Genus 59. Isoetes. Capsules placed in the axils of the 
ordinary rush-like leaves, those with large spores 
in the outer leaves, and those with small spores in 
the inner. Aquatic herbs. 
COHORT III. SPHENOPHYLLALES. 
ORDER VIII. PSILOTACEAE. Characters of the Cohort. 
Genus 60. Psilotum. Epiphytal, rigid, almost leafless plants, 
with much-twisted stems, repeatedly branched di- 
chotomously, and bearing the sporangiophores in 
the axils of the few small scattered leaves. 
COHORT IV. EQUISETALES. 
ORDER IX. EQUISETACEAE. Fertile cone terminal on the 
stem, and formed of numerous peltate receptacles, 
under the margin of which are placed the capsules, 
containing uniform spores, each with four hygro- 
metric filaments attached. 
Genus 61. Equisetum. Characters as above. 
