OF WESTERN PENNSYLVANIA 183 



short erect collum and narrowed above to a very small mouth ; 

 a low pseud-annuius present consisting of a number of layers 

 of cells ; outer peristome of one to several rows of short and 

 irregular teeth; inner peristome a pale, plaited, membraneous, 

 truncated cone, as in Diphyscium, 32-carinate ; spore-sac small, 

 surrounded by a large air-space ; spores small ; operculum small, 

 conic-obtuse, erect, falling tardily with the upper part of the 

 columella attached ; calyptra small, covering only the oper- 

 culum, glabrous, fugacious. 



A rather widely distributed genus of 5 species, 3 of which 

 occur in North America, one in our region. 



1. Buxbaumia aphylla Linnaeus, Hedwig. 

 (Plate XXVI) 



Plants minute on a thick, brownish, felted protonema and 

 after the development of the sporophyte usually completely 

 obscured by a dense growth of protonemal filaments : seta erect, 

 stout, rough, about 1 cm. high, castaneous ; capsule when ripe, 

 lustrous, castaneous, ovate-acuminate in outline, flattened 

 obliquely in the upper two-thirds, with angular edges, smooth- 

 ish, about 5-7 mm. long; operculum about 1.5 mm. high, 

 oblong-conic, disproportionately small ; calyptra falling early, 

 conic, covering only about one-half the operculum ; peristome 

 consisting of an outer series of papillose short, slender teeth, 

 and a longer, papillose, conical, plaited cone ; spores smooth, 

 spherical, about .007 mm. in diameter, mature in late fall and 

 early spring. 



On clayey and mud-covered banks in woods ; Europe, Asia, 

 and, in Xorth America, from Canada to West Virginia and 

 AYashington State." Rather rare in our region. 



Cameron : D. A. B. (Porter's Catalogue). 



Lawrence : On clay bank with decayed wood, under 



hemlocks and beeches, ravine three miles 

 north of Wurtemberg, October 16, 1910. 

 G. K. J. (Figured). 



Huntingdon : Boecking. (Porter's Catalogue). 



Family XXI. GEORGIACEAE. 



Autoicous : slender to very small, dull, gregarious to ces- 

 pitose, bright to brownish-green : stem erect, leaves 3-5-seriate, 

 unistratose, costa obscure to well-developed and ending just 

 below the apex ; cells parenchymatous, thick-\valled, smooth ; 

 perichsetial leaves larger : seta long, erect, straight or geniculate 

 in the middle ; sinistrorse below, dextrorse above ; capsule 

 erect, symmetric, smooth, oval or cylindrio; annulate; peris- 

 tome inserted below the mouth, consisting of the entire mass 

 of tissue enclosed within the operculum, this splitting by two 



