— 281 — 
1 VII. Hydrogonium C. Mueller. 
. 40.D.Ehrenbergii Lorentz. —- Trichostomum Lor.; Didymodon 
. Kindb.; Trichostomum (Hydrogonium) mediterraneum C. M. 
_ Leaves sublinear or ovate-lanceolate subobtuse not (or indi- 
 Süncetly near base) reflexed, patent when moist; basal cells 
narrow hyaline, the others smooth subpellucid sparingly chloro- 
 phyllose; costa not or scarcely excurrent. Capsules unknown. 
Stem often 3—6 c. m. high. — Wet calcareous rocks r. Eur. 
France; Taxis»: Boulay (Africa, Alger: Debat; Philibert). 
116. Pottia Ehrhart. 
À. Leaves smooth with hyaline cells. Paroecious. 
.P.venusta Juratzka. 
»Upper leaves long obovate-oblong spathulate short-acuminate 
not reflexed; costa excurrent. Capsule oval-cylindric; teeth 
none; annulus double persistent. — Hur.»: Schimper (»Asia 
island Cyprus: Unger»: Jur.). 
. $.P.pallida Lindberg. 
»Leaves recurved near middle, shorter than in the last. 
Capsule oval-oblong; annulus none. Smaller than the last. — 
Eur.r. Spain: J. Lange»: Schimper. 
B. Leaves often papillose; cells more or less chlorophyllose. 
a. Paroecious. Leaves us. reflexed and  papillose; ‘costa 
long-excurrent. 
 9.P.erinita Wilson. : 
_. Leaves broadly oblong-lingulate obtusate often obtuse, papil- 
lose and reflexed. Capsule us. suboval; teeth wanting orrudi- 
mentary; pedicel orange; calyptra us. smooth — Moist banks 
and rocks near sea r. Eur. Engl: Ralfs. 
* P.viridifolia Mitten; Braithwaite. 
"Lower leaf-cells shorter, the upper smaller. Peristome none. 
— Rocks near sea r. Eur. Irel.: Stewart. France: Le Jolis. — 
P.asperula Mitten; Braithwaite. | s 
 Leaf-cells as in P. crinita *viridifolia. Peristome none. Ca- 
 lyptra scabrous. — Eur. r. Engl: Curnow. 
.*P.Wilsoni Hooker. — Gymnostomum Hook.; Pottia Br. eur. 
Lower leaf-cells long narrow, the upper very small. Capsule 
“Narrower; teeth rudimentary. Calyptra scabrous. — Sandy 
 Pocky ground r. Eur. France: Lamy. Engl: Curnow. Amer. 
OU. S: Lesq. et Jam. 
.1P.euneifolia Solms Laubach. 
"Lower leaves linear-oblong, the upper longer and spathulate- 
oblong subobtuse smooth. r. reflexed. Capsule oval-oblong 
: 19 
