Family 3. SCHIZAEACEAE 
By WiiaM RaLPH Maxon 
Mainly tropical xerophilous plants of widely diverse form and habit. 
Sporangia superficial, borne singly or in rcws on narrow more or less special- 
ized lobes or terminal segments, or upon the very slender ultimate divisions 
of non-foliose pinnae, indusiate or non-indusiate, obovoid or pyriform (or, in 
the African genus Mohria, globose), provided with a definite subapical annulus 
or corona contracted distally, the sporangium dehiscing by a longitudinal 
fissure. Prothallia reniform to spatulate or more or less filamentous and 
branched, terrestrial. 
Fibro-vascular bundle of the rhizome central, solid. 
Fronds twining, elongate, dorsal, apparently inserted in a single row; 
spores triplanate. 1. LyGopium. 
Fronds upright or ascending, not twining, borne in several ranks; spores 
diplanate. 7 
Fertile segments spuriously digitate; sporangia apparently borne in 4 
more or less complete rows. 2, ACTINOSTACHYS. 
Fertile segments forming a pinnate spike; sporangia obviously in 2 
rows. 
Fronds mostly linear and simple, or, if dichotomous, the few slender 
divisions never forming a definite lamina. 3. SCHIZAEA. 
Fronds distinctly stipitate, the lamina repeatedly dichotomous, the 
divisions close and usually numerous. 4. LOPHIDIUM. 
Fibro-vascular bundle of the rhizome in the form of a reticulate tube. 5. ANEMIA. 
1. LYGODIUM Sw. Jour. Bot. Schrad. 18007: 106. 1801. 
Odontopteris Bernh. Jour. Bot. Schrad. 18002: 127. 2. 2, f. 4. 1801. 
Gisopteris Bernh. Jour. Bot. Schrad. 1800?: 129. 1801. 
Ugena Cav. Ic. 6: 73. 1801. 
Ramondia Mirb. Bull. Soc. Philom. 2: 179. 1801. : 
Hydroglossum Willd, Schr. Akad. Wiss. Erfurt. 1802: 20. 1802. 
Ctetsium Michx. Fl. Bor. Am. 2: 275. 1803. 
Lygodictyon J. Smith, Lond. Jour. Bot. 2: 284. 1842. 
Mainly plants of tropical and subtropical regions with slender vine-like twining fronds 
of indefinite growth, these borne dorsally and apparently in a single row upon a slender 
branched underground rhizome. Primary rachis wiry, more or less flexuous; leafy parts 
consisting of stalked subpalmately lobed, pinnate, or pinnately compound secondary pinnae 
arising in pairs from alternate slender or usually short naked stalks (the primary pinnae), 
with an included usually abortive bud, the primary pinnae thus pseudodichotomous. 
Sporangia strongly curved, laxly disposed in a row upon each side of the midvein of the 
contracted segments (sporangiophores), dorsal and solitary upon the simple pinnately 
arranged veinlets, protected each by a connate cucullate indusium formed of the modified 
leaf-tissue and opening antrorsely. Spores triplanate, yellow or whitish, smooth, verru- 
cose, or less commonly reticulate. 
Type species, Ophioglossum scandens 1. 
Sterile secondary (geminate) pinnae apparently subpalmate. 
Primary branches slender, elongate; secondary pinnae up to 6 cm. aes 
the lobes oblong to lanceolate, obtusish. 1. L. palmatum, 
Primary branches evident as short tubercles; secondary pinnae up to . 
25 cm. long, the segments linear-lanceolate, acute or attenuate. 2. L. radiatum, 
Sterile secondary (geminate) pinnae pinnate, the tertiary segments or divi- 
sions mostly petiolate. 
Tertiary sterile segments nearly equal. 
Veins free. 
Rachis of secondary pinnae strongly flexuous; tertiary segments . 
oblong-lanceolate. 3. L, volubile, 
VOLUME 16, Part 1, 1909] 31 
