compressed, mouth truncate, obsoletely four-lobed.
AndriEciiini terminal on the branches, bracts two
or three joined, except for the lobule somewhat
larger, scarcely differing from the leaves.
Sub-tribe II. PORELLEÆ.
Branches all lateral, intra-axillary ; lea\ es
incubous, lobules of equal size. Perianth
with the mouth lacinulate, at first constricted,
at length gaping and bilabiate. Capsule four-^
valved, the v a lve s often incompletely disconnected
at the base, ir regula r ly split.
G e n u s 5. PORELLA, Dill.
Branches lateral, intra-axillary, pinnate;
leaves incubous, deeply lobate. Per ianth at
first constricted, then g aping and two-lipped.
Capsule globose, rarely valvate to the v e r y
basé. Dill. Hist. Muse. ( 1 74 1 ) . Madotheca,
Dum. Comm. (1823) . Vide Sp ru c e Hep.
Ama z . p. 326.
Porella differs from all Radulæ in the regularly
pinnate and feather - like stems ; the axillary
branches (not infra-axillary, as in Radula, but intra-
axillary) ; the universal presence of underleaves,
the basal angles of which, like the external base of
the lobules, are often decurrent on the stem, in the
shape of a laciniate and críspate wing ; the side
leaves (especially on the branches) often subopposite
; the bracts of the male spikes exactly opposite,
and connate with the intervening underleaf,
the toothed or ciliated female bracts; the much
shorter and usually less compressed perianth, at
first constricted_ at the laciniate mouth, and only
becoming two-lipped or campanulate by the extrusion
of the fruit, the globose capsule, the valves
rarely separate down to the very base; the smaller,
shorter elaters, and the comparatively much larger
•¡.■^oxes.— Spruce.
Porella Isevig-ata, Schr.
Stem procumbent, bipinnately branched,
leaves broadly ovate, dentate, acute ; auricles
and st ipules oblong-quadrate, spinulosely-
toothed. Perianth dentate.
Jungermannia laevigata, Schrad. Samm. No.
104; Hook. Br. Jung. No. 35. Madotheca
laevigata, Dum. Comm., p. 1 1 1 ; Gott. and
Rab. Exs. 53, 259, 37 3 ; Co o k e Hep. f. 141.
Porella laevigata, Carr, and Pears. Exs. No.
45, 274, 275.
On the ground and on rocks.
Growing in loose patches. Stems procumbent,
flexuose, 2 to 3 or 4 inches long, with numerous
scattered lateral branches. Leaves at the base and
extremity smallest, everywhere in two opposite