!.] D I P L O P E R I S T O M I. 197 



Mnium pyriforme. Linn. Dill. Muse. t. oQ.f. 60. 



HAB. Rocks, especially of sandstone; likewise on the 



mould of garden pots. 



Bryum pyriforme is remarkable in the shape of its leaves, of 

 which the upper ones are much the longest and most flexuose. 

 They are composed, moreover, except at the very base, almost 

 wholly of nerve ; there being only a narrow membranous mar- 

 gin, which, towards the extremity, is deeply serrated. The 

 capsule and fruitstalk are of a bright orange colour when 

 mature. 



* * Leaves never subulate. 



f Leaves wit/tout any thickened margin. 



+- Leaves very obtuse. 



7. B.julaceum; stems branched, leaves closely imbricated broadly 

 ovate concave entire obtuse nerve running nearly to the 

 point, capsule obovato-eylindraceous pendulous. (TAB. 

 XXVIII.) 



Bryum j ulaeeum. Schrad. Spicil. p. 70. Smith, Fl. Brit. p. 1357. 

 Engl Bot. t. 2270. Hook. Fl. Scot. P. II. p. 149. Am. Disp. 

 Muse. p. 45. 



Bryum argenteum. /3. Linn. Sp. PI Schwaegr. Suppl. v. 1. P. II. 

 p. 188. 



Hypnum argenteum. /3. Mohr. Dill. Muse. t. 50. f. 63. 

 HAB. Mountains in England, Scotland, and Ireland. 

 The characters above given we have found constant in this 

 plant, and we therefore cannot agree with Mohr and Schwae- 

 grichen, who, following Linnaeus, have considered it as merely 

 a variety of B. argenteum. It is not in the shape of the leaf 

 and of the capsules only that they differ, but our individuals are 

 . taller and more slender, of a yellowish green colour, resembling 

 that of Hypnum stramineum, and the foliage is of the same 

 colour and texture throughout. This species is never found on 

 walls and roofs of houses, as is commonly the case with B. 

 argenteum , but on the sides of streams in mountainous situa- 

 tions. 



N 3 



