GRiMMiACEiE.] 78 [Orthotriclmin. 



Autoicous ; in loose dull green or olivaceous tufts, i — i in. high. 

 Leaves imbricated when dry, recurved when moist, oblong-lanc, rather 

 obtuse, recurved at margin ; cells above very small, subhexagonal or 

 rounded, incrassate, with i — 2 simple or rarely bifurcate papillae, basal 

 rectangular, smooth ; nerve vanishing below the apex, channelled 

 above. Caps, immersed, rarely exserted, pale olivaceous brown, oval- 

 oblong, rounded at base and suddenly narrowed into a very short pedicel, 

 urceolate when dry, with 16 ridges, the alternate ones shorter, or rarely 

 with 8 only, each composed of 2 — 3 rows of quadrate yellow incrassate 

 cells ; stomata immersed, the border cells elevated, not covering all the 

 stomatic cells. Annulus of 2 — 3 rows of compressed cells ; lid shortly 

 apiculate, pale yellow, orange at margin. Peristome simple, pale yellow, 

 rarely with traces of cilia, teeth when dry spreading horizontally, never 

 recurved, 16 geminate, with 4 basal lamellae to each, reaching to second 

 or third joint, or sometimes much higher, surface traversed by faint 

 sinuose longitudinal lines. Calyptra swollen, campanulate, plicate, 

 naked or with some hairs, brownish or ochraceous, rusty at apex. Male 

 infl. pseudolateral, bracts ovate, obtuse. 



Hab. — Rocks and walls in limestone districts. Fr 4 — 5. 



Var /8. nudum (Dicks.) 



Tufts more laxly pulvinate, deep green. Caps, partly or entirely exserted, 

 attenuated at base into a longer narrower neck, teeth more distinctly 

 striolate, with the external appendages more developed. Calyptra more 

 conical, naked or with a few hairs. 



bvx. — Ottlwtrichum nudum Dicks. Crypt, fasc. IV, 7, t. 10, f. 13 (1801). Sm. FI. brit. 1268. 

 Eng. Bot. t. 1325. Turn, muse, hib. 97, Brid. Sp. muse. II, 12; Mant. iii. Vent. 

 in HusN. muse. gall. 161, t. 45. 



O. cummtitatum Bruch in Brid. Bry. un. i, 784. 



O. Rudolphiamim Lehm. in Flora 1827, p. 656. 



0. Floerkei Hornsch. Brid. Bry. un. i, 783. 



O. cnpulatum y. riparium Hueben. muse. germ. 381. Schimper, &c. 



0. cnpulatum Var. nudum Braithw. 



Hab. — On stones by the side of streams. 



Tanfield, Clapdale and Bolton Abbey, Yorks. (Baker 1856). Lewes (yenner). Balcombe 

 (Mitten). By the Hodder, Clitherce (Wood i860) ! ! Litton, Yorks. (Whitehead and 

 Ashton 1&78) ! ! Miller's dale and Monsal dale (Holt 1884) ! ! Brigsteer, Westmoreland 

 (Barnes) ! 



This species most resembles 0. rupestre, but is easily separated by the 

 shorter pale capsule with immersed stomata, 16 striae, and different peristome ; 

 the var. nudum is usually of a lurid or blackish green tint, reminding us of 

 0. rivulare. 



