ORTHOTRICHUM. 175 



OETHOTEICHUM, Hediv. (Bristle Moss.) 



"A peculiar and yet natural genus/^ the species being 

 very similar in the appearance of their leaves and branches. 

 From the peristome varying much in its nature, it is neces- 

 sary, in examining the plants, to have the capsule in good 

 condition. Weber and ]).Iohr, in their 'Botanical Handbook/ 

 say "that there is scarcely any genus more beautiful, and 

 not many more diiftcult." The name of the genus is derived 

 from the circumstance of the calyptra being in most of the 

 species well covered with " straight hairs," like some species 

 of Poli/irichum. 



Generic Character. — Seta terminal. Peristoine mostly double ; 

 the outer of sixteen teeth, approaching in pairs ; the inner of as 

 many cilia, lying horizontally (sometimes wanting). Calyptra 

 mitriform, furrowed, more or less hairy, 



^ Peristome single. 

 t Capsule immersed. 

 1. Orthotrichum cuiulatum, Hoffm. {Single-fringed 

 Sessile-fruited Bristle 3Ioss.) Leaves ovato-lanceolate, 

 erecto-patent, w^hen dry erect, straight, rigid ; capsule nearly 

 sessile, furrowed for its whole length, quite glabrous. — Eiig. 

 Fl.p. 53; Mull. Si/n. 2^1. l.^j. 700. 



