irregular. Antheridia embedded in the frond, cylindrical, hyaline ;
style projecting, hyaline.
D imensions.— F ronds about ¿ inch long by about ¿ inch
wide ; capsule 'Co mm. diam. ; spores '08 mm. diam.
H ab.—On very damp earth in fields, on wet banks, or
especially by the margin of ponds. Very rare.
3. In a ditch near Deptford, Kent, Peiiver, now extinct.
4. Helford, West Norfolk, Rev. E. N. Bloomfield, Aug. 1881
5. Stoke-on-Trent. P. Garner; Pottal Reservoir, Warwickshire,
J. E. Bagncdl. 7. Dolgelly, Merionethshire, J. Balfs, 18C3 ;
Aberilraw, Anglesey, IE. Wilson. 8. Exposed mud banks of
reservoirs at Cropstone and Thornton, Leicestershire, F. T Moll
Aug. 1894. 9. Mere Mere, Cheshire, G. E. Ihmt, I 869’.
13. Brownhall Orchard, Dumfries, J. Cruickshank ?
Pound on tlie Continent and in North America.
Obs. This rare and distinct species may be distinguished
from R. glauca by its larger size, paler and yellower colour
spongy texture and its antical surfiice being pitted with deei!
cavities.
I t has been conjectured that it might be a terrestrial form of
Rtcciocarpus nataus, but, in addition to its otlier distinguishiuo-
charaoters, the spores are nearly twice as large and are reticulate
not papillose.
Desciuption op P late CCXVIL—Figs. 1-4.
size. 0. Frond x . 6. Cross-section of frond
8. Portion of frond x . 9. Eootlets x . 10.
11. Capsule X. 12. Style x . 13. Spores x
frond, showing styles of antheridia.
'(Lindenherg).
Plants natural
X . 7. Ditto.
Calyptra x .
14. Portion of
15. Styles of antheridia X
3. Riccia sorocarpa, Bischoff.
Piccia soi'ocarpa, Bischoff, Hep. Nov. Act. N. Car. xvii. p. 1053, t. 71, f. 11
(1835).
Piccia minima, L. Schiffn. in Engl, und P ran tl Pflanzenf. 91 und 92 Lief. p.
15 (1893).
Piccia minima, L. p.p. Howe, Hep. & Antho. Calif, p. 23 (1899).
Monoicous, cæspitulose, small, pale green in colour, when
dry albescent, concolorous. Fronds subradiate, bifurcate ; lobes
■oblong-linear, on cross-section boat-shaped, sulcate, deeply so
when dry, with margins erect ; margins thin, smooth, or with
few hyaline scales ; apex acute or obtuse ; texture firm, antical
surface finely reticulate. Capsules embedded in the irond,
roundish, dark brown. Spores reddish-brown, walls thin, finely
tuberculate on the convex sides, projections very minute and
numerous.
D imensions.—Fronds about 4’ inni, long; lobes '75 m m .
broad x '75 m m . thick, 1' mn i . x '75 m m . , I ' l n m . x '6 mm . ;
when dry '6 m m . broad x 1' inm. thick, '75 m m . x '9 m m . ,
•8 m m . X '5 m m . ; spores 'OG.o m r a . , '08 m m . x '055 m m .
H a b.— On thin rocky soil, or more rarely in cultivated fields in
limestone districts. Rare.
1. Battery Hedge, near Penzance, Cornwall, W. Curnow, Sept.
1879. 5. Gt. Doward Hill, B. IL IT'alkins, Sept. 1879 ; Cheddar
Clifls, near Ross, Herefordshire, B. IL Watkins. 7. Barmouth,
Merionethshire, W. II. P., Aug. 1877. 8. Millers Dale, Derbyshire,
W. II. P., Jan. 1879. 12. On earth, among rocks, near
Levens Church ; Whitbarrow; in sandy cultivated fields S.W. of
Bridge End, Levens, Westmorland, G. Stabler.
I. In fissures and tops of old walls ; on an old wall near
Dingle, Lindberg fl Moore, 1873; wall top by the roadside,
leading from Dingle to Ventry, the Dingle side of the river near
the Union, Lett fl McArdle, ls9S.
Found on the Continent and in North America.
O b s .—From any form of Riccia glauca L. distinguished by its
deeply sulcate lobes, when dry, being apparently thicker than