256 



HANDBOOK OF BRITISH MOSSES. 



narrow, oblongo-lanceolate from a slightly expanded base ; 

 margin reflexed below ; pcrichsetial leaves convolute ; sporan- 

 gium slightly ovato- oblong, curved; lid subulate; ring dis- 

 tinct. Hook. 8) Wils. t. xii. ; Eng. Bot. t. 2382. ; (Moug. fy 

 Nest. n. 716.) 



On walls and banks, especially in calcareous districts. Bear- 

 ing fruit in summer. 



Forming large, short, yellow-green patches. Leaves crisp 

 when dry ; nerve ceasing at or near the tip ; more translucent 

 than the disk ; fruitstalks of a beautiful pale-yellow, slender ; 

 teeth much twisted ; basal membrane narrow ; leaf-cells above 

 minute, filled with chlorophyll, gradually increasing in size to 

 the basal disk, those at the wings large and rectangular. 



16. T. revoluta, Hook, fy TayL ; dioicous, subpulvinate ; 

 leaves erecto-patent, rather obtuse, lanceolate, imbricated and 

 somewhat twisted when dry ; nerve thickened above and 

 slightly excurrent ; margin strongly revolute ; perichsetial 

 leaves loosely sheathing ; veil large ; sporangium oval-oblong ; 

 lid oblique ; ring simple ; basal membrane narrow. Hook, fy 

 Wils. t.\\\. ; (Moug. fy Nest. n. 218.) 



On walls, especially in limestone districts. Bearing fruit 

 in April. 



Forming pale, dense, yellowish-green patches. Stem 

 scarcely more than J- an inch high ; fruitstalk reddish ; spo- 

 rangium rather small. Scarcely ever growing on the ground. 

 Distinguished at once by the differently-coloured fruitstalk, 

 simply sheathing perichsetial leaves and their revolute margin. 

 Leaf-cells larger than in the last, nerve much thicker. 



17. T. Hornschuchiana, Wils.; dioicous; loosely tufted; 

 leaves spreading, somewhat recurved, incurved or spirally im- 

 bricated whe^n dry, lanceolate, keeled, acute ; margin revolute ; 

 nerve excurrent, rather slender,; perichsetial leaves loosely 



