DKYEI. 195 



pointed, bluntish ; margin revolute; sporangium oblong, more 

 or less pendulous, not shining. Hook, fy Wils. t. xlviii. 



On moist mountainous rocks. Devonshire. Bearing fruit 

 in September. 



Differs from B. alpinum in its olive-green tint, broader 

 bluntish leaves, with larger leaf- cells, and its rusty or bay, not 

 purple sporangia. 



16. B. csespiticium, L. ; dioicous ; stem branched and 

 innovated, radiculose; leaves erecto-patent, erect and straight 

 when dry, lanceolate or oblongo-lanceolate ; margin mostly 

 entire, reflexed, concave; nerve excurrent, forming a long 

 hair-point; sporangium oblong, obovate, pendulous, slightly 

 constricted below the mouth when dry ; lid large, mammillary. 

 Hook. Wils. t. xxix. ; Eng. Bot. t. 1904. ; (Moug. $ Nest, 

 n. 134, 929.) 



On walls, rocks, the bare ground, etc. Bearing fruit in 

 early summer. Forming little dense tufts of a pale green. 



A very common and variable plant as to the direction and 

 serrature of the leaves, shape of the sporangium, etc. 



17. B. argenteum, L. ; dioicous; silvery-white, tufted ; 

 upper leaves closely imbricated, ovato-lanceolate, very concave, 

 entire, apiculate ; nerve not excurrent ; leaf- cells large ; 

 sporangium oval-oblong, pendulous; lid mammillary. Hook, fy 

 mis. t. xxix. ; Eng. Bot. t. 1602 ; (Moug. $ Nest. n. 133.) 



On the naked soil, walls, roofs, etc. Extremely common ; 

 cosmopolitan. Bearing fruit in. winter and early spring. 



Forming little patches, conspicuous for their silvery colour, 

 and the closely imbricated leaves with colourless tips. Spo- 

 rangium purplish or reddish, constricted below the mouth 

 when dry ; lid convex, slightly pointed. 



18. B. capillare, Hedw. ; dioicous ; leaves more or less 

 spreading, strongly twisted when dry ; upper leaves obovate 



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