BARNES — NORTH AMERICAN MOSSES. 185 



II. Costa scabrous or lameUose at hack. 

 Leaves with pellucid hair points .... C. introflexus, 78. 

 Leaves not hair pointed. 



Alar cells round, lamina wanting .... C. frigidus, 79. 



No auricles C. Virgi ulcus, 80. 



FISSIDENS, p. 8i {incl. Conomitrium, p. 89.^) 



1. (EUFISSIDENS.) Plants terrestrial or submersed but not float- 



ing; leaves soft, one layer of cells. 



A. Fruit terminal. 

 I. Monoicous, male flowers axillary. 



[F. falcatulus may be sought here.] 



Leaf-cells small, densely chlorophyllose, in distinct rows F. limbatus, 82. 

 Leaf-cells large, not densely chlorophyllose, nor in dis- 

 tinct rows F. bryoides, 81. 



2. Dioicous or monoicous with the male flowers terminal on a root- 



ing branch at the base of the female stem. 



a. Leaf-cells 1^-2 times as long as wide, large, distinct. 



Plants less than 1 mm, high, leaves two or three pairs F. Closteri, 81. 



Plants 2-4 mm. high, wholly hyaline, leaves 3-5 pairs F. hyaliuus, Si. 



b. Leaf-cells almost or quite isodiametric, often obscure. 



[F. linibatns may be sought here.J 



Leaves with a narrow border, at least on vaginant lamina. 

 Marginal leaf -cells not papillose. 

 Leaves acute, costa percurrent. 



Vaginant lamina not reaching middle of leaf, peris- 

 tome arising below the mouth . . . F. pusillus, 94. 

 Vaginant lamina reaching middle of leaf, peristome 



not arising below the mouth . . . F. incurYUS,^ 82. 

 Leaves obtuse, costa vanishing below apex F. obtnsifolius, var. 95. 



1 See Barnes: Bot. Gaz. 12: 1. 1882. 

 ' See Appendix, no. 93. 



