21. POTTIA. Ehrh.
116. P. pusilla. Hedw. (P. cavifolia. Ehr.) St. very short and simple or branched; l. erecto-patent concave, obovate or elliptical; caps. oval, on a short seta; lid obliquely rostrate.
Banks and mud walls. III.
var. β. stem short, l. somewhat acuminate, scarcely piliferous. γ. incana. N. & H. l. with long hair-like points.
117. P. minutula. B. & S. Very minute, l. carinate, spreading, ovate-lanceolate, with recurved margins; caps. small, ovate-truncate; lid flattish conical, not beaked.
Fallow fields. Winter and Spring.
var. β. rufescens. l. narrower reddish. γ. conica. l. ovate-lanceolate, with a short mucro, caps. narrower at mouth.
118. P. truncatula. L. St. ⅛in., l. spreading obovate-acuminate or oblong-lanceolate, with a slightly excurrent nerve; caps. obovate, truncate, with a wide mouth; lid convex obliquely rostrate.
Fallow soil. II. III.
var. β. major. caps. oval-oblong, stem smaller. γ. sub-cylindrica. l. ovate-lanceolate; nerve much excurrent; caps. sub-cylindrical.
119. P. crinita. Wils. St. ¼in. tufted; l. obovate-oblong obtuse; nerve excurrent into a very long hair-like point; caps. elliptic-oblong, scarcely contracted, calyp. smooth.
Rocky and moist places.
120. P. Wilsoni. B. & S. St. ¼in. in tufts, l. ovate-oblong, obtuse; nerve excurrent into a longish mucro; caps. elliptic-oblong, contracted at mouth; lid shortly and obliquely rostrate; calyp. rough at apex.
Sandy banks. II.
121. P. littoralis. Mitt. (Jour. Bot. IX., 4.) L. oblong-spathulate obtuse or acute, lower pale, upper green, nerve excurrent, longer in lower leaves; areolæ in upper part of leaf small obscure, smooth, lower oblong pellucid; caps. oblong-oval, mouth less than greatest diameter; lid rostrate slightly twisted; male fl. bud-like.
Aldington, near Brighton, Hastings.
122. P. asperula. Mitt. (l. c.) L. obovate-spathulate, acute, but not acuminate, nerve excurrent into a short point; areolæ upper rounded rather obscure, each with several elevated points, lower oblong smooth pellucid; caps. oval, lid rostrate slightly twisted; antheridia naked in axils of comal leaves.
Henfield, Sussex; Penzance (Curnow), Jersey (Piquet).
123. P. viridifolia. Mitt. (l. c.) (P. pallida, Braith. Jour. Bot. VIII., 255, non Lindberg.) L. obovate-spathulate obtuse or slightly acute; nerve not very stout, excurrent into a short point; margin recurved at middle; areolæ, upper hexagonal or nearly square, obscure, with minute protuberances, lower oblong hyaline smooth; caps. oblong on a short seta; lid rostrate; antheridia in axils of comal leaves.
Plymouth (Holmes).
124. P. Heimii. B. & S. St. ⅛–¼in. cæspitose, branched; l. spreading, oblong-lanceolate, margin not recurved; caps. obovate or oblong truncate, lid obliquely rostrate, adherent to columella.
Moist banks near the sea. IV. V.