24 MUSCI-ACROCARPI-PERISTOMI. [Grimmia. 



at Aberdour, and Glen Tilt, Scotland. The teeth of the peristome are 

 slightly oblique at the first falling of the lid. (Wits.) 



19. W. acuta, Hedw. (sharp-pointed Weissia); stems branched, 

 leaves subulato-setaceous subsecund rigid canaliculate, capsule 

 turbinate, lid rostrate. Hedw. St. Cr. v. 3. t. 35. Drum. Muse. 

 Scot. v. 1. n. 30. Muse. Brit. ed. 2. p. 87. t. 14. — Grimmia 

 acuta, Turn. Muse. Hib. p. 29. Fl. Brit. p. 1192. E. Bot. 

 t. 1644 — Weissia rupestris, Hedw. Sp. Muse. t. 14. — Bryum 

 acutum, Dicks. — B. splachnoides, Dill. Muse. t. 47. /. 34. 



Moist alpine rocks, abundant. Fr. Summer.— The leaves are remark- 

 ably rigid, when dry, of a shining brownish-green. The capsule has a 

 swelling at the base, somewhat resembling an apophysis. Small speci- 

 mens of Dicranum fulvellum bear a slight resemblance to this moss, 

 and in the first edition of Muse. Brit., they were injudiciously confounded, 



15. Grimmia. Ehrh. Grimmia. 



Seta terminal. Peristome of 16 entire or perforated, rarely- 

 cleft, equidistant teeth. Calyptra mitriform. (Muse. Brit. t. 2.) 

 — Named in honour of Dr. F. C. Grimm, author of some 

 botanical writings — This genus bears the same relation to 

 Weissia, that Trichostomum does to Didymodon : its essential 

 distinguishing character residing in the mitriform calyptra. 

 This is accompanied by a peculiarity of aspect in the whole 

 plant, which is of a singularly lurid blackish-green colour, the 

 leaves often tipped with diaphanous points. 



* Fruit sessile or nearly so. 



1. G. apocdrpa, Hedw. (sessile Grimmia); stems branched, leaves 

 ovato-lanceolate recurvo-patent their margins reflexed, those of 

 the perichsetium having the nerve disappearing immediately 

 below their summits, capsule ovate sessile, lid shortly rostrate. 

 Muse. Brit. ed. 2. p. 65. t. 13. — a. nigro-viridis; leaves broad 

 blackish-green. G. apocarpa, Hedw. St. Cr. v. 1. 1. 39. Turn. 

 Muse. Hib. p. 20. FL Brit. p. 1200. E. Bot. t. 1134. Drum. 

 Muse. Scot. v. 1. p. 26. — G. alpicola, Swartz, Muse. Suec. t. 1. 

 Hedw. Sp. Muse. t. 15. Fl. Brit. p. 1199. — G. rivularis, Brid. 

 in Schrad. Journ. v. 5. t. 3. Turn. Muse. Hib. p. 21. t. 2. /. 2. 

 Schwaegr. Suppl. v. 1. t. 23. Fl. Brit, p, 1200 G. gra- 

 cilis, Schwaegr. Suppl. v. 1. t. 23. — G. apocaula, Hoffm. — Dill. 

 Muse. t. 32. — (3. stricta; stem elongated, leaves narrower red- 

 dish-brown. — G. stricta, Turn. Muse. Hib. p. 20. t. 2. f. 1. 



a. On trees and moist places, as well as in alpine rivulets. — /3. rocky 

 places in elevated mountains. Fr. Spring. — A very abundant and highly 

 variable plant. The leaves have sometimes diaphanous points, at 

 other times they are destitute of them. The var. stricta is the most 

 remarkable state, with slender elongated stems and of a reddish brown 

 colour. The columella is slender upwards. 



2. G. maritima, Turn, (sea-side Grimmia); stems short pul- 

 yinate, leaves lanceolate acuminate nearly erect crisped when 



