70 BRYACEAE 



B. argenteum L. A small species, growing everywhere; 

 usually in dense mats. It is especially fond of dry compact 

 soil in sandy fields and waste places. It grows abundantly in 

 paths and between the bricks of sidewalks in towns and cities. 

 When full grown it is a bright silvery gray. Autumn. 



RHODOBRYUM (Schimp.) Hampe 



Nearly always dioicous. Very large plants, the largest 

 and showiest of all this family. The stems spring from stolons, 

 and are nearly leafless except at the summit, where the very 

 large leaves form a rosette. Under favorable circumstances 

 large mats are formed on old rotten logs or at the base of trees 

 in rich peaty soil. 



R. roseum (Weis.) Limpr. "On decayed wood, on the ground 

 about the roots of trees and on moist rocks, frequent," Muse. 

 App. 203. Apparently occasional about the city, Closter, 

 Yonkers, Bronx Park; Todt Hill, S. Id. 



Subfamily 2. Mnieae 



Plants usually larger than in Subfamily I , with larger broader 

 leaves. Leaf cells nearly as broad as long. Plants rarely 

 branching by innovations below the "flowers," frequently 

 stoloniferous, i. e., with prostrate or creeping sterile shoots that 

 root at their tips. Capsules usually without appreciable neck; 

 stomata usually immersed or partially so, rarely completely 

 superficial. 



MNIUM (Dill.) L. (Plate VII. Fig. 2.) 



Plants usually large with large leaves, which are broadly 

 oblong, or obovate to Ungulate, the lower nearly always shorter 

 and more rounded than the upper, usually with a strong dis- 

 tinct border which is often strongly toothed. Costa usually 

 percurrent or nearly so, sometimes shortly excurrent. Leaf 

 cells rounded-hexagonal to quadrate-hexagonal, somewhat larger 

 and elongated at base, not papillose. Calyptra small, cucul- 

 late. Capsules oblong-cylindric to ovoid, pendent, not pyri- 

 form; operculum mammillate to rostrate. Peristome perfect; 

 cilia often nodose but not appendiculate. 



