1903] ODONTOSCHISMA MACOUNITI AND ITS ALLIES 341 
2. Odontoschisma Gibbsiae, sp. nov.—Plate XIX, figs. 29-34. 
Plants yellowish green, more or less tinged with red or brown, 
growing in depressed mats or creeping among other bryophytes: 
stems sparingly and irregularly branched, 0.3™™ in diameter, 
prostrate, ascending at the tips; flagella postical or terminating 
leafy branches; vegetative branches varying from postical to 
lateral; rhizoids scanty: leaves imbricated, strongly concave, 
increasing in size from the base of a leafy axis, orbicular, 1™ 
long, not bordered, attached by an oblique line of insertion, 
slightly decurrent antically and more or less dilated at postical 
base, arching to or beyond the middle of the axis, margin entire, 
apex rounded: leaf-cells 16X23 at edge, Ig in diameter in 
the middle and 23 at the base, with very large and occasionally 
confluent rounded trigones; cell cavities stellate with distinct 
pits; pigmentation when present limited to the lining of the 
cavity, not affecting the limiting membrane of the pits nor the 
outer part of the very thick smooth or minutely verruculose 
cuticle: underleaves minute, except at the base of a branch, 
irregular in shape, sometimes vaguely bidentate: inflorescence 
unknown: gemmae and gemmiparous branches similar to those 
of O, Macounii but the latter with more loosely imbricated leaves. 
On a log. British CoLuMBIA: Port Renfrew, Vancouver Island (J/iss 
Gertrude Gibbs), the type locality. 
3. ODONTOSCHISMA DENUDATUM ( Mart.) Dumort. Recueil d’Obs. 
sur les Jung. 19. 1835.—Plate XIX, figs. 35-38. 
Jungermannia scalaris, var. 8 denudata Martius, F1. Crypt. Erlangensis 
183. 1817. 
Jungermannia denudata Nees; Martius, of. cit. praef. p. xiv. 1817. 
Pleuroschisma (Odontoschisma) denudatum Dumortier Syll. Jung. Eur. 
69. 1831. 
Sphagnoecetis communis B macrior Nees, G. L. & N. Syn. Hep. 149. 1845. 
Sphagnoecetis Huebneriana Rabenhorst, Deutschlands Krypt.-Flora 2: 
338. 1848. 
Odontoschisma Huebnerianum Aust. Hep. Bor.-Amer. 61b. 1873. 
Cephalozia (Odontoschisma) denudata Spruce, On Cephalozia 61. 1882. 
Odontoschisma Sphagni 8 denudatum Massal. & Carest. Nuovo Gior. 
Bot. Ital. 14: 238. 1882. 
dontoschisma Sphagni var. macrior Meylan, Bull. de l’Herb. Boissier 
Il. 1:629. Igor. 
