2 THE HANCOCK PACIFIC EXPEDITIONS VOL. 3 



Fissidens (Semilimbidium) Hancockiana, sp. nov. 

 Plate 1, figures 1-3. 



Planta 5-10 mm. alta, erecta, atro-vel pallido-vlrldis, vetustate 

 fuscescens; folia 13-25 juga (pares 2-5 infima valde minores), 

 lanceolata, apicibus acutis serrulatis; vaginarum laminae marginatae, 

 foliis 2/5 breviores; costa crassa tenuiter vel haud flexuosa, percur- 

 rens; marginis cellulae perlongae angustaeque, hyalinae sed aetata 

 decolorantes; cellulae ceterae parvae, 5-7 ix diametro, mamillosae 

 papilla centrali singulari, ita ut marginem crenulato-denticulatum 

 simulans et areolas obscurans; cellulae apicium ultimae laevigatae 

 et valde maiores, haud papillosae; lamina inferior haud decurrens. 

 Autoica; antheridia sub perichaetio; archegonia in cauli primo ter- 

 minalia, vel in gemmis axillaribus, vel in ramosis axillaribus perbre- 

 vibus aut elongatis; fructus singularis vel nonnunquam duplex; seta 

 vetustate rubra, 2-4 mm. longa, flexuosa; capsula subobliqua vel 

 horizontalis; urnula 0.6-0.7 mm. longa; cervix stomatosa; operculum 

 rostratum urnulam aequilongum. 



Plants of small to medium size, 5-10 mm. high, erect, somewhat 

 caespitose, stiff^, increasing in size each year by a resumption of 

 growth at the apex of the stem, or through the development of 

 axillary, dorsal, easily separated innovations, or both, the old stems 

 finally becoming prostrate, bearing several erect secondary branches; 

 dark to yellowish-green, turning reddish-brown with age, the stem 

 and costa becoming red even in rather young plants; leaves in 13-25 

 pairs, the lowest 2-5 pairs smaller than the others, 1.0-1.5 mm. long, 

 0.2-0.3 mm. wide, oblong-lanceolate, tapering rather gradually to 

 a straight or very slightly falcate acute and serrulate apex, with a 

 conspicuous border on the sheathing laminae, extending slightly 

 beyond their juncture, the sheath reaching about three fifths of the 

 way to the apex; terminal leaves only slightly or not at all larger 

 than the others, all with a stout, rarely slightly flexuous costa which 

 is percurrent or very nearly so; the cells of the border are very 

 long and narrow, hyaline or pale yellow, becoming colored in old 

 leaves; the remaining cells small, 5-7 ix in diameter, each cell mamil- 

 lose, with a single high, central papilla, so that the unbordered leaf- 

 margin is crenulate-denticulate and the areolation somewhat obscure, 

 except at the serrulate apex where the cells are about twice as large 

 and not papillose; inferior lamina ceasing abruptly at the base, not 

 at all decurrent. Autoicous; the antheridia in a very short, bud-like 



