Jennings: Manual of Mosses — 30. Hookeriaceae 215 



hypnoid, large, the teeth tather broadly lance-acuminate, densely trabeculate, 

 the lower trabeculae often forked and thus united by obliquely transverse bars, 

 the dorsal lamellae numerous and below densely cross-striate, yellowish; seg- 

 ments as long as teeth, carinate but rarely split, the basal membrane about 

 one-third as high as teeth, the cilia 3, nodose or appendiculate above, nearly 

 as long as segments; spores mature in winter, about .018-. 022 mm, medium- 

 walled, yellowish, granular; annulus large. 



In wet, grassy fields, swamps, and bogs; Asia, and from New England to 

 Ontario and south to Illinois and probably rather common in the northern 

 part of our region. 



Allegheny Co.: Swampy ground near Douthett, about on boundary line of Butler 

 and Allegheny counties, April 26, 1908. O.E.J. Bedford Co.: In swamp along Rays- 

 town Branch, Juniata River, south of Schellsburg. July 19, 1941. C.M.B. Butler Co.: 

 Svv?mpy ground near Crider's Corner's April 26, 1908. O.E.J. Crawford Co.: Pyma- 

 tuning Swamp, near Linesville, June 12, 1905. O.E.J, (figured). Erie Co.: On decay- 

 ing log in swamp, Presque Isle. Nelle Ammons. Aug. 3, 1935. 



la. Helodium paludosum var. HELODioiDES (Renauld and Cardot) Best 



{Thuidtum elodioides Renauld and Cardot) 



Leaves smaller with margins dentate-serrate, the cells more or less strongly 



and often sub-centrally papillose; darker green; cells shorter, elliptic or oval. 



In swampy meadows, swamps, bogs, etc.; from New York to Ohio and 



Indiana. Apparently rare m our region. 



Family 30. HoOKERIACEAE 



Soft, often complanately foliate; leaf-cells smooth, thin-walled, mostly 

 parenchymatous, alar not differentiated. 



A large family of about 700 species mostly tropical and on trees or decay- 

 ing wood. Only Hookeria in our region, with one species. 



1. Hookeria acutifolia Hooker 



(Pterygophyllum lucens SuUivant (1864), not Bridel (1819); 

 Pterygophyllum acuminatum Paris) 



Plate LXVII 



In large, soft, light green mats with somewhat complanate foliate branches 

 5-10 mm wide, in ours about 2-3 cm long. When dry, the leaves are thin, 

 soft, translucent, lustrous, and yellowish. Leaves ovate to oblong-ovate, acute, 

 4-5 mm long, entire, slightly decurrent, the lateral somewhat unsymmetric, the 

 apex often slightly eroded, sometimes producing protonemal filaments; leaf- 

 cells somewhat irregularly oblong-hexagonal, somewhat shorter at basal angles 

 and at apex and slightly narrower along the margin, the median about 3-5:1. 

 Not found fruiting in our region. 



On earth and rocks in cool wet situations. Connecticut to Ohio and the 

 southern Appalachians. 



Fayette Co.: Ohio Pyle on rock below Cucumber Falls, wet with spray. O.E.J. &C 

 G.K.J, and Dr. and Mrs. W. H. Emig, May 12, 1917 (figured); on dripping shaded 



