378 Mr. R. Spruce on the Musci and Hepatice of the Pyrenees. 
240. T. vinealis, Brid. Br. Univ. 1. p. 880 (sub Barbula) ; Br. 
Europ. J. c. p. 24. t. 10. 
Var. 8. flaccida, Br. EKurop.; M. P. 184.—Hab. Z, P. ce. ad 
ripas rivuli qui ad monasterium Médous prope B.-de-Bigorre ori- 
ginem suam habet. 
Var. nivalis, M. P. 185.—Hab. Z, in rupibus frigidis ab aqua 
nivali irrigatis vallis alpme Hsquierry dicte. 
This second variety forms large compact tufts on the ledges of 
dripping rocks, growing near Senecio Tournefortii, Huphrasia minima 
and Luzula spadicea. 'The stems attain a length of 6 or 8 inches, and 
are clad throughout with leaves of a deep reddish brown. Hence its 
aspect is very different from that of the ordinary form of T. vinealis, 
but without the fruit I do not venture to separate it. 
41. Didymodon, Schwegr. (ex parte). 
241. D. rubellus, Hoffm. Deut. Fl. 2. p. 33 (sub Bryo); Br. 
Europ. Didymodon, p. 3. t. 1; M. P. 186. . Weisia curvirostra, 
H. et T.! Muse. Brit. p. 84. t. 14. 
Hab. Zy_2 in muris, rupibus, &c. 
242. D. cylindricus, Bruch in Brid. Br. Univ. 1. p. 806 (sub 
Weisia) ; Br. Earop. /. c. p. 5. t. 3; M. P. 187. 
Hab. Z, P. occ. in saxis rivulorum supra thermas dict. les Haue 
Bonnes; P. ¢. in vicinia B.-de-Luchon, frequens, locis Superba- 
gneéres, Lac de Séculéjo, Cascade du Ceur, &c. 
42. Trichostomum, Hedwig. 
Obs. T. flewicaule is the only species of this genus which seems 
absolutely confined to calcareous rock: 7’. mutabile, crispulum and 
tophaceum were observed on no other rock in the Pyrenees, but in 
England I have occasionally seen them in habitats where no trace of 
carbonate of lime was to be detected. The last five species form 
part of the genus Leptotrichum of Hampe, and are placed by C. Muel- 
ler in his tribe Leptotrichacee (Conf. Syn. Muse. p. 415). 
§ 1. Crispuia. 
243. T. mutabile, Bruch mst. ; Br. Europ. Trichostomum, p. 8. 
t.5; M. P. 188. | | 
Hab. Z, locis caleareis. P.oce. ad pagum Narcastet. P.c. in 
rupibus umbrosis prope B.-de-Bigorre (Chemin de Labassére et 
Bains de Salut). An revera a sequente distincta species ? 
244. T. crispulum, Bruch et Muell. in Regensb. Bot. Zeitung, 
1829; Br. Europ. l. c. t.4; M. P.189. Didymodon Benthamit, 
Arnott! in Edinb. New Philosoph. Journ. 1846. 
Hab. Z, in rupibus calcareis irroratis Pyren. occidentalium, 
frequens. Pau; Narcastet, &c. Restincliéres prope Montpellier 
(Arnott !). 
