﻿7. GLEICHENIA. § 3. MERTENSIA. a. DICRANOPTERIS. 59 



coriaceous; surfaces naked or the under one tornentose on the costulae like 

 the rachises. — The description is taken from specimens gathered in Amboyna 

 by Boerlage, determined by Christ. 

 Borneo, Celebes, Batjan, Amboyna. 



* (7) G. lineariis, ClarUe, Trans. Linn. Soc, Bot., S*" Series, 1,428; 

 G. dichotoma, Hk., Rac, Flor. Biz., I, 13; Bedd., Ferns S.I., tab. LXXIV; 

 G. Hermanni, R. Br., Bl., Enum., 248; Polypodiiim lineare, Biirm., (oldest name); — 

 var. rigida, Rac, 1. c. ; — var. normalis, Rac, 1. c; — var. ferruginea, Rac, 

 1. c; G. ferruginea, BL, Enum., 249; — var. emarginata, Christ, Ann. Btz., 

 XV, 77; — var. malayana, Christ, 1. c 



Fronds large, + 3 — 4 X dichotomous, each forking bearing a pair of 

 deflexed, unbranched branches at the base on the outer side, except the ter- 

 minal forkings, which are commonly without accessory lateral branches. Ultimate 

 branches mostly with numerous + spreading segments on each side. — 



Forma typica: Textui'e subcoriaceous ; surfaces naked, not glaucous. Ul- 

 timate segments under 4 c.M. long. 



"Vap. rigida: Texture rigidly coriaceous. 



War. normalis: Under surface glaucous. 



Var. ferruginea: Under surface clothed with ferrugineous, furl'ura- 

 ceous tomentum, at least on the costae. 



Var. emargina ta : Texture very rigid ; under surface clothed 

 troughout with ferrugineous hairs. 



War. malayana: Very large; branches much elongated, with the 

 ultimate segments 4 — 6 c.M. long or longer. 



Tropical and extra-tropical. 



* (8) O. laevigata, Jlfc., Rac, Flor. Btz., I, 11; G. bifurcata, BL, 

 Enum., 2S0; ? G. flagellaris, Spr., Christ, Farnkr. d. Erde, 342. 



Stipes terete or nearly so, often narrowly marginate. Fronds large, 

 repeatedly dichotomous; the lowest forkings divaricating or rectangularly 

 spreading, not rarely nudate. Ultimate segments linear, to 5 c.M. long, to 2 '/, 

 m.M. broad, horizontally spreading, obtuse or retuse. Texture ± herbaceous; 

 upper surface bright-green, under one paler, naked, or the costae cobwebby or 

 tornentose with ciliate, ferrugineous scales. Sporangia ± 3 — 4. — G. flagel- 

 laris, Spr., which has the under surface very glaucous, is probably another 

 species very near our plant, but not malayau. 



Malaya. 



