Jennings: Manual of Mosses — 4. Fissidentaceae 69 



dorsal wing: seta shorter than the perichaetial leaves, flexuous or cygneous; 

 capsule spherical, oval or obovate, smooth; no peristome or annulus; spores 

 .015-.02C mm; operculum abruptly and irregularly rostrate; calyptra smooth, 

 covering, about one-third of the urn; antheridial plants similar in appearance 

 to the archegonial. 



Three species; one in Mexico, one in Asia, and one in Europe, Korea, and 

 the United States, rare. 



1. Bryoxiphium norvegicum [Bridel] Mitten 



(Eustichia norvegica Mueller) 



Plants 1-2.5 cm long, somewhat flexuous, flat, lustrous, yellow, fastened to 

 vertical sandstone cliffs by a rac'iculose bulbiform base; stems mostly simple; 

 leaves short-acuminate and as described for the genus; costa vanishmg at or 

 near the apex: seta rather thick, about 2 mm long; capsule obovate, pale yellow, 

 mouth reddish, peristome none; operculum reddish at base, attached to colum- 

 ella and long-persistent; calyptra cucullate, large, tipped with a slender beak. 



On shaded vertical exposures of sandstone in Greenland, and in a few 

 widely separated localities from Minnesota to western Pennsylvania and 

 Tennessee. 



Lawrence Co.: "Slippery Rock Creek, Lesquereux." (Porter's Catalogue). The 

 writer has not been able to find this species along Slippery Rock Creek, where Lesquereux 

 found it. 



2. FissiDENS Hedwig 



Autoicous or dioicous: stem short to long, erect to procumbent, more or 

 less branched or simple; leaves prominently winged, linear-obovate to lanceolate- 

 obovate; costa usually present; cells rounded-hexagonal, sometimes loosely 

 rhomboidal, rarely prosenchymatous, smooth or papillose: seta erect or ascend- 

 ing, lon-^ to short, mostly terminal, sometimes lateral; capsule mostly exserted, 

 erect or inclined, symmetric or unsymmetric; peristome mostly inserted below 

 the mouth of the urn, teeth cleft, exteriorly articulate, often striate-papillose; 

 spores m.ostly small; operculum conic to rostrate; calyptra entire to once or 

 rarely several times cleft, mostly smooth. 



A. widely distributed renus of about 700 species, mainly tropical, on soil, 

 rocks, trees, humus, or in water. In our region at least 8 species. 



Key to the Species 



A.Costa none: minute plants 2-4 mm high L F. hyalinus 



A. Costa well developed B 



B. Leaves bordered, at least on the vaginant lamina of the perichaetial leaves, by a 



band of linear cells C 



B. Leaves not bordered, or at least the border not composed of linear cells G 



C.Costa percurrent, confluent with border at apex and forming a mucro: capsule erect 



2. F. hryoides 



c. Costa not usually percurrent, or only so in upper leaves; border not usually reaching 



apex: capsule curved or erect D 



D. Leaves non-bordered, entire, obtuse 3. F. obtusifolius 



D. Leaves bordered, at least on sheath of the perichaetial leaves, acute or apiculate E 



E. Leaves bordered to near the apex F 



E. Leaves usually bordered only on the sheath of the perichaetial leaves 5. F. exiguus 



