THE FAMILIES, GENERA AND SPECIES OF PTERIDOPHYTA. 475 



Family Nl.—GLEICHENIACEJE. 



Vernation circinate. Sori dorsal. Indtisium absent. 

 Sporangia few (generally 4 to 8j, large sessile, with a broad, 

 transverse, complete ring, dehiscing" longitudinally. — Small 

 plants with creeping" rhizomes. The leaves are dichotomously 

 branched, which distinguishes them from all other South 

 African ferns. 



I. Gleichenia, Smith. 



Sori terminal on the veins. Leaf-texture more or less 

 coriaceous or chartaceous. 



Pinnules barely longer than broad; sori at the apex of 

 a veinlet. (Eii-glcichcnia). 

 Leaves i to 3 ft. long"; pinnae i to 4 in. long. 2 to 3 

 lines wide; pinnules i to i^ lines long, i line wide. 



1. polypodioidcs. 

 Pinnules much longer than broad ; sori medial on the 



veinlet. (Mcrtcnsia.) 

 Primary branches of the rachis bearing pinnules, l)ut 

 not subtended by small, lateral pinnated pinnae. 



2. nmbraculifcra. 

 Primary branches of the rachis naked, but subtended 



by a pair of small, pinnated pinnae arising from 



each fork 3. dichoioina. 



1. (/'. polypodioidcs. Smith. — Alamotsuiri, Ze., Juiwd 213; 

 Rustenburg, R., Miss Collins, in T.M.H. y/y. 



2. (/. unibraculifcra, Moore. — Forming" dense masses on 

 steep, grassy banks, often fully exposed to the sun. Near 

 Lydenburg", Ly., Dr. Atherstonc; Pilgrim's Rest, Ly., Roe; 

 Mamotsuiri, Ze., Jiuwd 209; Barberton, Bn., =5,500 ft.. Thorn- 

 croft 365, in T.M. H. 



3. (/'. dichotoma, Willd. — Mauchsberg, Ly., Burtt-lhwy 468; 

 Houtboschberg, Ze., Miss Eastzvood. 



Family Yll.— OSMUND A CE.E. 



Vernation circinate. Indusium absent. Sporangia shortly 

 stalked, with a very incomplete horizontal ring, opening" by a 

 longitudinal fissure at the apex. — Short-stenmied plants. 



Sori on special pinnae i. Osmunda. 



Sori on backs of ordinary pinnae 2. Todea. 



I. Osmunda, Linn. Royal Fern. 



Lower pinnae, (in ours) leafy and barren. LIpper pinnae 

 reproductive only, forming" a sort of panicle, densely covered 

 with sori. Sori with a peculiar ring consisting" of a round 

 group of cells at one side of the apex. Indusium absent. 

 Sporangium dehiscing" longitudinally. — Rootstock bearing 

 scale leaves below the soil and ordinary leaves above. Other 

 species (not South African) have fertile pinnas on the lower 

 part of the leaf; others again have separate vegetative and re- 

 productive leaves. 



I. 0. rcgalis, Linn. — Along streams and in damp places, 

 often in full sunshine. Pilgrim's Rest, Ly., Roc, Bolus 1,732; 



