Analytic Keys to the Species of Mosses. 
35 
b. Leaf-cells almost or quite isodiametric, often obscure. 
Leaves with a narrow border, at least on vaginant lamina. 
Marginal leaf-cells not papillose.F. incurvus, 3. 
Marginal leaf-cells papillose. 
Costa percurrent.F. Ravenelii, 13. 
Costa ceasing below apex.F. Garberi, 15. 
Leaves without a border. 
Acute, cells densely chlorophyllose, obscurely papillose F. Donnellii, 14. 
Obtuse, cells pellucid, operculum conic . . F. obtusifolius, 17. 
Apiculate, operculum with acicular beak . . F. osmxmdoides, 18. 
Leaves with a thick reddish border. Plants submersed, 
rigid . . F. rufulus, 8. 1 
B Fruit lateral. 
1. Leaves without a border. 
Obtuse, entire, plants 2-5 cm. high, fruit sub-terminal F. polypodioides, 23. 
Rounded at apex, irregularly serrate, 1-2 cm. high, fruit 
sub-basal.F. sub-basilaris, 22. 
Mucronate, regularly serrulate, fruit basal or sub-basal F. taxifolius, 20. 
2. Leaves bordered by several rows of paler, often incrassate, cells. 
Capsule cernuous, leaf-cells minute F. Floridanus, 7. 
Capsule erect or inclined, flowers dioicous, leaf-cells ob¬ 
scure . F. decipiens, 19. 
Capsule erect or inclined, flowers monoicous, leaf-cells dis¬ 
tinct .F. adiantoides, 21. 
II. (PACHYFISSIDENS.) Leaves rigid, composed of more than one 
layer of cells, opaque. 
Plants growing in water or very wet places . . F. grandifrons, 24. 
III. (OCTODICERAS.) 2 Plants aquatic, filiform, floating. 
Plants large, much branched, pedicel shorter than the 
capsule. F. Julianas, C. 1. 
Plants small, little branched, pedicel longer than the cap¬ 
sule . F. Hallianus, C. 2. 
1 F. ventricosus, Lesq. 
2 Conomitrium of Manual. 
