112 HYPNACEAE 



(R. & C.) Grout, although some of the branch leaves are serru- 

 late. Autumn-winter. 



PLATYGYRIUM B. & S. 



The microscopic structure of this genus is so like that of 

 Entodon that I placed it in that genus in my monograph (Bull. 

 Torr. Bot. Club 23: 227), but the dark-green scarcely glossy 

 appearance and the small terete branches much more closely 

 resemble Pylaisia than Entodon. 



From Pylaisia this species is distinguishable by the fact that 

 the leaves are not at all falcate-secund and the branches are 

 little if any curved at the ends. The ends of the branches often 

 bear gemmae in the axils of the leaves. 



P. repens (Brid.) B. & S. On bark of trees, on logs and 

 stumps. Frequent. Smithtown and Jamaica, L. Id.; Willow 

 Brook!! and Todt Hill, S. Id.; Bronx Park, Pelham Parkway, 

 Yonkers; Closter. Autumn. 



PYLAISIA B. & S. (Not Desv.) 



A genus of tree-growing mosses sometimes found on fallen 

 trunks, usually easy of recognition by reason of their slender 

 branches, curved when dry and almost hooked at the ends by 

 reason of the falcate-secund leaves and also by their small erect 

 and cylindric capsules, having very degenerate inner peristomes; 

 cilia lacking (or very rudimentary in polyantha) and often having 

 the segments adherent to the teeth. The leaves are ecostate 

 or with costa short and double, concave, entire or slightly ser- 

 rulate above. The annulus is much narrower than in Platy- 

 gyrium or Entodon (except E. sednctrix). 



Key 



1 — Segments of endostome free from the teeth subdenticidata 



Segments of endostome wholly or partially adherent to the teeth .... 2 



2 — Segments partially adherent; spores 18-24.JX Schimperi 



Segments wholly adherent, 25-70^ intricate 



P. intricata (Hedw.) R. & C. {P. velutina Schimp.) Van 

 Cortland Park, E. G. B., Bx!; "On trees in swamps and in 

 mountainous regions, N. J.," Muse. App. 293; Yonkers, E. C. 

 Howe. 



