GRIMMIA. 141 



mitriform, lobed. Peristome teeth lanceolate, deeply divided 

 into two, rarely three, filiform branches. Autoicous ; male 

 flowers axillary. 



Hab. Siliceous rocks, at low elevations ; not common. Fr. summer. 



Easily known by its robust habit and rough, long hairs, the autoicous inflorescence, 

 the sinuose areolation, etc. The last character is somewhat variable however, as is 

 also the amount of roughness of the hair-points, and forms occur linking it with the 

 sub-species G. robttsta. G. elatior has still longer leaves with smoother points, and is 

 dioicous. 



* Grimmia robusta Ferg. (G. decipiens var. robusta Braithw., 

 Brit. M. Fl.) (Tab. XXII. G.). 



Closely resembling G. decipiens, but differing in the darker 

 tufts, the stems less branched ; the leaves smaller, with the hair- 

 point shorter, smooth or nearly so, the cells short, rectangular 

 and sinuose almost to base, only a few rows near the nerve being 

 narrow and elongated. Fruit not seen. 



Hab. Rocks. Rare. 



Braithwaite is no doubt right in uniting this with G. decipiens, though where sub- 

 species are admitted it is probably worthy of the higher rank. It also comes very 

 near G. trichophylla in some of the forms of that moss, but the cells are more dis- 

 tinctly sinuose, and the colour different from what is usual in that species. 



14. Grimmia elatior B. & S. (Tab. XXII. H.). 



Tall and robust, 1-3 inches high, in lax tufts, the stems 

 easily separating, naked and decumbent at base, repeatedly 

 dichotomous ; grey or yellowish green above, blackish below. 

 Leaves erecto-patent, appressed when dry and straight or turned 

 to one side, very long, from a wide oblong base gradually 

 lanceolate, carinate-concave, 1— if lines long, one margin strongly 

 revolute, the other less so or plane, sometimes obscurely 

 toothed near apex, hair-point short, about \-\ length of leaf, 

 smooth or slightly denticulate, narrow at the base, nerve strong, 

 prominent at back. Basal cells yellowish, narrow-linear, elon- 

 gate, strongly sinuose and incrassate, a few rows at margin 

 short, rectangular, thin-walled ; above the cells rapidly shorten, 

 becoming very sinuosely rectangular, then quadrate and 

 irregular, small, incrassate , all sinuose, opaque, in two or three 

 strata near apex, irregularly papillose. Dioicous. Seta short, 

 curved, pale ; calyptra mitriform ; capsule rather large, pale 

 brown, oval-oblong, sulcate when dry; lid rostellate ; teeth of 

 peristome bright red, irregularly divided, closely articulated. 



