282 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 12 



NITOPHYLLUM Greville, 1830 



Plants forming delicate flat membranous blades, dichotomously or 

 subpalmately forked or lobed, lacking any veins, monostromatic except 

 in the older or fruiting parts, without cross-dividing apical cells except on 

 juvenile plants and proliferations; tetrasporangia in evident rounded 

 sori ; spermatangia in elongated sori ; cystocarps scattered, with the carpo- 

 spores generally single on the ends of the gonimoblasts, enclosed in a 

 pericarp. 



KEY TO SPECIES 



1. Blades with a few broad, divaricate, tapering lobes, commonly 

 fimbriate on the margins ^ N. divaricatum 



1. Blades with numerous segments, frequently redividing, the final 

 segments commonly ligulate and about 1 cm wide .... 



N. galapagense 



Nitophyllum galapagense n. sp.^'^^ 



Plate 94, Figs, 1, 2 

 Plants to 35 cm tall, the base small and disciform, the stalk less than 

 1 cm long, the thallus above phylloid, dull rose red and delicate, nitent 

 when dry; from a cuneate base, ovate or with a few elongate segments, 

 dissected, the divisions ligulate to subspatulate or cuneate, redivided 

 above, the margins in some specimens beset with ovate stipitate to sessile 

 ligulate sterile proliferations, the larger proliferations and the tips of 

 main branches ending in rounded ligulate lobes about 1 cm broad ; growth 

 by scattered marginal cell initials, not by a cross-dividing apical cell; 

 intercalary cell divisions present; thallus in the central region 1-3 cells 

 thick, with a rather thick cuticle ; veins and veinlets absent, except for a 

 vaguely defined thickening in the middle quite near the base ; reproductive 

 structures rather evenly distributed over the blades except near the base, 

 the tetrasporangia in irregular oval or sublinear sori about 1 mm diam., 

 1-2 mm long; spermatangia in irregular oval sori 1-2 mm wide, 2-4 mm 

 long, notably dull in appearance in the dried specimens; cystocarps 1-2 

 mm diam., in section showing the carpospores terminal on the branching 

 gonimoblasts. 



i"S Nitophyllum galapagense n. sp. — Planta ad 35 cm altitudine, stipite minore 

 quam 1 cm Ions;., lamina phylloidea e basi cuneata, nitente, ovata aut in segmeptis 

 paucis elongatis incisa, divisionibus ligulatis ad subspatulatas, supra redivisis, 

 cacuminibus divisionum primariarum in lobos rotundatos ligulatosque circa 1 cm 

 latitudine terminantibus; thallo 1-3 cellularum crassitudine, cuticulam manifestam 

 habente; soris tetrasporangialibus irregulariter ovatis aut sublinearibus, ad 1 mm 

 diam., 1-2 mm long.; spermatangiis in soris ovatis 1-2 mm lat., 2-4 mm long.; 

 cystocarpis dispersis 1-2 mm diam. Planta typica in loco dicto I. Santa Cruz, Ecua- 

 dor, legit W. R. Taylor no. 24-318 A. 20 Jan. 1934. 



