32 APLOPERISTOMI. [Tetraphis. 



Mohr in separating it from Buxbaumia, under which it had so 

 long been arranged ; and thence follows the necessity of placing it 

 in a different part of the artificial arrangement. 



1. D. foliosum. (TAB. VIII.) 



Diphyscium foliosum. Mohr, Obs. Bot. p. 34. Hook, in Fl. Lond. 

 new series, (cum Ic.). Moug. et Nestl. n. 11. Funck, Deutschl. Moose, 

 t. 24. / 1. *Hook. Fl Scot. P. II. p. 123. Hobson, Brit. Mosses, v. 

 1. n. 14. Drummond, Muse. Scot. v. I. n. 6. Am. Disp. Muse. p. 12. 

 Brid. Meth. p. 123. 



Buxbaumia foliosa. Linn. Syst. Veg. p. 945. Hedw. Sp. Muse. p. 

 166. Smith, Fl. Brit. p. 1148. Engl Bot. t. 329. 



Buxbaumia sessilis. Schmid. Diss. de Buxb. p. 26. t. 1. / 124. 

 Ditt. Muse. t. 32. / 13. 



HAB. Woods, on Banks, and Wall tops in alpine situa- 

 tions. 



The plant grows in excessively dense, matted patches, closely 

 interwoven together by means of their numerous fibrous roots. 

 The leaves are small, ligulate, of a dark green colour, opaque, 

 furnished with a strong nerve. The perichcetial leaves are large, 

 erect, membranous, pale brown, covering entirely the capsule, 

 lanceolato-oblong, acuminated, and towards the extremity, cut, 

 in a singular manner, into long slender segments at the margin ; 

 nerve strong, rigid, brown, very excurrent, serrulate at the 

 extremity. Capsule nearly sessile, large, ovate, gibbous, ob- 

 lique. Calyptra mitriform. Lid conical, acuminated. Peri- 

 stome simple, consisting of a whitish plicate membrane forming 

 a truncated cone. 



VIII. TETRAPHIS. 



GEN. CHAR. Fruitstalk terminal; Peristome single, consist- 

 ing of four equidistant upright teeth; Calyptra mitri- 

 form. (TAB. I.) 



A genus confined to a very small number of species ; of a rigid 

 habit ; the lid of the capsule is remarkably thin and membranaceous, 



