FISSIDENTACEAE. 99 
§ Semilambidium C. M.—Very small, mostly dull green, terrestrial plants. 
Leaves facta ee only on the vaginant lamina, or very faintly elsewhere ; 
margins of the superior and dorsal lamina usually crenulate-denticulate. 
Cells oat Poe finely papillose and opaque. Seta and peristome as 
in Bryoidiu 
PF. vittatus H. f. & W. 
F. anisophyllus Dixon. 
F. abbreviatus Mitt. 
§ Aloma C. M.—Small terrestrial mosses. Leaves thin, unbordered, more 
or — ig oe at margin. Cells hexagonal, pellucid. Seta and peristome 
in Bryowdium. 
PF. tenellus H. f. & W. 
F. aeruginosus H. f. & W. 
§ Amblyothallia C. M.—Plants of middle size, with mostly elongate stems. 
falcate or enrolled when dry, un ered, almost entire. Cells small, obscure 
or pellucid. Seta terminal. Branches of peristome-teeth papillose, rarely 
obscurely nodose. 
F. pallidus H. f. & W. 
F. oblongifolius if Pew: 
F. asplenioides Sw. 
§ Serridium C. M.—Middle-sized to very robust plants; stem elongate. 
Leaves large, not bordered, often with a paler margin of more pellucid 
cells, usually broadly pointed, mostly denticulate or serrate above. Set 
usually lateral. Branches of pcnged -teeth nodosely thickened. 
F.. adiantoides (L.) Hedw 
Subgen. OcropicEeras (Brid.) Mitt. —Weak, soft, floating plants; stem 
without. vautial strand ; seta short, lateral, or from a short lateral branch, 
minute, symmetrical, oval ; cy 9 conical, usually entire at base. 
F. Miilleri (Hampe) Mi 
poe sore os. will gaat characterize the two species 
dealbatus and F. Miilleri, and I have not included them in the 
fcllownn 
The Meiiukien between the sections Bryoidium and Semilimbidium 
are not always well defined, and plants with a faint border to the upper 
part of the leaf should be tried in both divisions of § 3 of the key. 
Key To THE Spectres or EUFISSIDENS. 
¢ | Doves ee ee —, narrow, confined to eat = of leaf, or me 6. Taylori. 
rmal.. Pe 2 
: — Bee a edad cian at ek on a vaginant ia re a 3 
= {ie Leaves without a hyaline border ‘ ie Ja AD 
Leaf distinctly bordered throughout one. ae he ee ae 4 
at ” anisophyllus, and leptocladus may be sought as ce — a 8 
a) _ iat: with — —— border stout. es gee ade 
hes ery sm sisi, ee etrical, very 0 items 
Gals ane larger, irregularly Thana more pelle, lax and elongate i in in vaginant 
Stem short, iokinen 3 in few pairs, nerve oe border peer waicns —s 
Stem elongate, leaves a , tigid, erect; stout nerve and bond very 
a pellucid, reac x and confluent in point gonioneurus. 
