570 THE ORTHOTRICHE^ OF YORKSHIRE. [October, 



exserted, oblong, with, 8 distinct strise; teeth 8, bifid. Lime- 

 stone walls^ etc. Spring. 



2. O. cupulatum, Hoff. Capsule immersed, obovate, with 16 

 strise; teeth 16; calyptra convex, hairy. Limestone districts; 

 common. Spring. 



/S. nudum ; capsule exserted, calyptra naked. By streams. It 

 is sometimes found on stones in streams liable to inundation, and, 

 like other Mosses in such places, acquires a lurid tint. It may be 

 distinguished from 0. rivulare by the acute leaves, capsule with 

 16 ribs, and single peristome. Sometimes cilia are present in 

 luxuriant specimens. 



** Peristome double, outer of 8 teeth, rejlexed when dry. 



I. PumiLjE. Capsule of thich texture, ribs 8, prominent, as broad as the 

 interspaces ; lid with a short beak ; spores small, brown.* Stems 

 sparingly branched, forming small erect tufts (except 9), i to | in. 

 high, on hedges and exposed trees. 



a. Leaves acute. 



3. 0. tenellum, Bruch. Leaves narrow, lanceolate, erect when 

 dry ; capsule exserted, subcylindrical, full brown ; cilia 8 ; 

 calyptra narrow, conical, yellow, slightly hairy. June. York, 

 Sutton, Thirsk, Ay ton in Cleveland, Bolton, Hkley, etc., Wharf- 

 dale. 



Stems slender, ^ inch long, simple or bifid. Upper leaves 

 scarcely larger than the rest, of a pale pellucid green, erect when 

 dry. " This is one of the most beautiful species, easily recog- 

 nized by its narrow, elongated, golden-brown capsules, which are 

 strongly ribbed when dry, and by its narrow, glossy, yellow 

 calyptra.^' (Bry. Brit.) The calyptra in all the allied species 

 is broad and campanulate. Vaginula naked, surmounted by a 

 larger ochrea than usual ; this is sometimes torn when old, and 



* The study of tliis section is beset with peculiar difficulties. The smaller 

 species (except those with obtuse leaves) being frequently overlooked as varieties 

 of O. affine. If attention is given to the above characters they may be at once 

 separated. The capsule in FumilcB is stronger ; \mder the microscope the ribs 

 are found to consist of four rows of large quadrate cells, as broad, or broader than 

 the intermediate portion, wliich is formed of about four rows of smaller, oblong 

 ceUs ; — whereas in AffincB the ribs are narrower, and the interspaces composed of 

 about eight rows of cells, nearly double their width. The hd in PmnilcB is small, 

 with a broad, ill-defined, reddish border, and a short beak ; in Affince the lid is 

 conical, with a long beak, and narrow scarlet border. 



