326 
Descriptions of New British Species 
and Varieties, 
Riccia Crozalsii Levier. 
The following is a translation of Dr. Levier’s Latin description, 
contributed by D. A. Jones, F.L.S. 
“ Monoicous, slender, 2—3 mm. long, 0-34—0-75 mm. wide, 
glaucous green except at the margins and dark-coloured apices, 
simple or bifid. Fronds in linear segments, obtusely elongate-ovate, 
apices acute and deeply sulcate, canaliculate, margins tumid, 
fringed with two rows of cilia about 034 mm. long more or less 
inflected. Ventral scales at the apex of the frond hyaline, small, 
those along the postical sides dark purple. Tranverse section 
at the apex of the frond almost as broad as high, at the middle 
semi-circular, dorsal surface with two fairly deep channels, middle 
segment convex, margins ascending almost vertically. Upper layer 
chlorophyllose, occupying about a third part of the thickness of the 
frond. Antheridia mostly about the apex, not easily detected; 
ostioles small 120-130 y. long, discoloured, projecting out of the 
middle depression. Sporangia quite numerous on the same frond, 
often two in the same tranverse section ; style very dark, slightly 
protruding above the epidermis. Spores 65—85 y. opaque, dark 
brown, border narrow, entire or sparingly and minutely granular- 
papillose. Areolae numerous 8—12 along the diameter. Rhizoids 
hyaline with very numerous papillae within. Epidermal cells not 
incrassate or mamillate.” 
Aplozia csespiticia (Lindenb.) Dum. 
Dioicous : pale yellowish green, caespitose, stems closely prostrate 
with numerous whitish rhizoids, ascending at the tips, mostly simple 
but often innovating below the perianth and occasionally bearing a 
lateral branch ; leaves imbricated, concave, obliquely inserted, 
broadly orbicular, rounded or slightly emarginate at the apex, 
slightly decurrent at antical base, margins entire or subcrenulate 
from projecting cells : leaf-cells with very thin walls, scarcely or not 
at all thickened at the angles ; walls of marginal cells sometimes 
thickened along free edge of leaf; cuticle smooth, underleaves 
