Mosses and Lichens 



Annulus. Double. 



Spores. Mature in spring. 



Distribution. Headquarters in the Mediterranean basin; 

 rare in England, common in the western states of 

 North America. 



Tortula ruralis. 



Tortula ruralis is much like the 

 preceeding, but smaller, with flowers 

 dioicous. It grows on thatched 

 roofs or stony ground, in tall 

 cushions I to 3 inches deep; bright 

 green above and bright red- 

 brown below. The awn at the apex of 

 the leaf is strongly spiny, transparent 

 above and often red at the base, some- 

 times equalling the rest of the leaf. 

 The spore cases are narrowly cylin- 

 drical with a lid half as long and a 



T. ruralis. Tip , ,. , 



of spore-case, (a) StOUt red pedicel about 3tt inch long, 

 basilar mem- T. ruralis. 



brane , (6) twisted Awn at the apex 



teeth. of the leaf. 



Genus GRIMMIA, Ehrh. 



The species of the Genus Grimmia sometimes form con- 

 spicuous gray tufts, often hoary from the white hair-points which 

 terminate the leaves; sometimes they form soft fragile patches on 

 exposed rocks of higher mountain regions. The tufts vary in 

 size from little dense cushions one-third of an inch high, to the 

 mats of Gr. bypnoides, whose stems attain a length of eight inches. 



The dingy colour of their leaves, tipped with long or short 

 white hairs is their most striking character. The chlorophyll is 

 not only absent from the hair-point but often from the apex of the 

 leaf-blade as well, thus adding to the grayish-white appear- 

 ance of the tufts. The plants are usually short, with forked 

 stems, crowded with lance-shaped leaves, frequently thick- 

 ened along the margin, which is mostly entire; the vein is 

 percurrent or extends into the transparent hair; the cells 

 of the lower part are rectangular, of the upper part small, 

 often obscure. 



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