SYNOPSIS OF THE SPECIES. XXXI 



254. Pluma; minute, rising from creeping filaments; stems erect, simple or 

 branching ; branches naked below, pinnated above ; pinnae erect, opposite, 

 close; tetraspores globose, on short processes of the pinnules. (Tab. 

 CCXCVI.) 



* * Stems shrubby, robust, more or less opake. Ramuli alternate. 



255. arbuscula; stems shrubby, opake, naked below, robust, much branched ; 

 branches densely set on all sides with minute imbricated plumules ; ultimate 

 pinnules simple or forked, recurved, their articulations twice as long as 



• broad; tetraspores glolfbse, lining the inner face of the pinnules. (Tab. 

 CCLXXIV.) 



256. Brodisei; stem subopake, veiny, obscurely jointed, slender; branches 

 lateral, patent, closely set with quadrifarious secondary branches ; plumules 

 simply pinnate, the pinnae sometimes ramulose at the tip ; tetraspores oval, 

 sessile near the tips of the pinnules ; favellae bilobed, on the secondary 

 branches. (Tab. CXXIX.) 



257. tetragonum; outline of the frond ovate; stem thick, setaceous, opake, 

 veiny, set with quadrifarious, lateral branches ; penultimate branches arti- 

 culate, set with short, alternate, level-topped plumules ; pinnules incurved, 

 constricted at the base, suddenly acuminate, their articulations once and 

 half as long as broad; tetraspores very minute, oval, subterminal. (Tab. 

 CXXXVI.) 



258. brachiatumj character of C. tetragonum, except that the lowermost plu- 

 mules are reduced to subulate ramuli ; and the pinnules are not constricted 

 at base, and taper gradually (not suddenly) at the apex. (Tab. CXXXYII.) 



259. tetricumj rigid, shrubby; stem and branches robust, shaggy below, plu- 

 mulate above ; plumules crowded, simply pinnate ; pinnae acute, tapering 

 at the base, erecto-patent ; articulations twice or thrice as long as broad ; 

 tetraspores elliptical, minute, sessile on short lateral processes of the pinnae. 

 (Tab. CLXXXVIII.) 



260. Hookeri; stem setaceous, nearly opake, pinnatedly much branched; 

 branches decompound, spreading, flexuous, densely plumulate ; plumules 

 naked below, pinnate or sub-bipinnate above, the pinnae horizontal or diva- 

 ricating, ramulose at the tips; articulations 2-3 times as long as broad ; 

 tetraspores numerous, sessile on the pinnules. (Tab. CCLXXIX.) 



* * * Main stems slender, evidently jointed ; branch's decompound-pinnate. 

 Ramuli alternate. 



261. roseumj much and loosely branched ; secondary branches long, flexuous, 

 distichously plumulate; plumules lax, simply pinnate; pinnae long, spread- 

 ing, curved; articulations 4-5 times as long as broad; tetraspores elliptical, 

 secund, four or five on each pinna. (Tab. CCXXX.) 



262. byssoideumj exceedingly slender, and flaccid, decompound; plumules 

 long, flexuous, pinnate or sub-bipinnate ; articulations of the branches 

 eight, of the ramuli four times as long as broad; tetraspores one or two, 

 sessile near the base of the pinnules. (Tab. CCLXII.) 



263. polyspermum ; tufts globose ; filaments slender, much branched, secondary 

 branches distichously plumulate ; plumules long and narrow , -imply pinnate; 

 pinnae short, simple, spine-like, patent ; articulations 4-5 times as long as 

 broad; tetraspores globose, lining the inner face of the pinna 1 . (Tab. 

 CCXXX I.) 



264. purpurascens, Sm. E. Bot. t. 2465. (Unknown to me.) 



