130 A MANUAL OF MOSSES 



2. Acaulon rufescens Jaeger. 

 (Phasciini rufescens Kinclb. ) 



Plants minute, bulbiform, about 1 mm. high, yellowish- 

 green, not markedly triquetrous : protonema persistent ; lower 

 leaves very small, ecostate, the upper much larger, broadly 

 ovate, deeply concave, convolute, plane-margined, erose-denticu- 

 late at apex ; in larger leaves the costa thick, excurrent into a 

 squarrose-recurved apiculus ; leaf-cells about as in A. triquetrum : 

 seta flexuose or arcuate ; capsule globose, smooth ; calyptra and 

 spores similar to those of A. triqiictruin. 



On bare clayey or sandy soil in moist fields, Eastern and 

 Central North America. 



Indiana : Deny. James. (Porter's Catalogue, as 



Sphaerangiiuii uniticuui [Schreber] Schim- 

 per). 



3. PHYSCOMITRHLLA Bryologia Europsea. 



Paroicous, rarely synoiccus : protonema sparse and disap- 

 pearing early: minute, gregarious, somewhat succulent: stem 

 mostly low, simple, without central strand ; upper leaves 

 rosette-like, spreading, obovate, acute to acuminate, plane- 

 margined, bluntly serrate ; costa ending below the apex ; leaf- 

 cells very lax, rhomboid above, the lower rectangular and 

 sparsely chlorophyllose : seta rudimentary ; capsule sub- 

 globose, without collum, apiculate ; operculum hardly distinct 

 but capsule usually splitting equatorially ; cells of capsule- 

 wall large, hexagonal, thin-walled ; the large columella even- 

 tually completely absorbed ; spores large, papillose ; calyptra 

 narrowly campanulate. 



A genus of but 2 species : P. hainpci Limpricht, in Europe, 

 and the following: 



1 . Physcomitrella patens Hedwig] Bryologea Enropcea. 



(Phascuin patens Hedwig). 



Gregarious, pale green : stem distinct but very short, about 

 2 mm. ; leaves lance-ovate to oblong or oval, usually shortly 

 and bluntly acuminate, the upper often obovate-acuminate 

 and larger, forming a rosette, all serrate above; costa narrow, 

 ending below the apex; leaf-cells lax, widely rectangular to 

 hexagonal : seta short, capsule globose, thin-walled, usually 

 splitting equatorially, brownish, immersed to slightly emer- 

 gent, obtusely apiculate; spores papillose, .025-.030 mm., ma- 

 ture in autumn : paroicous ; antheridia sessile in upper leaf- 

 axils. 



On wet clayey or sandy soil in fields, along sides of pools, 

 river banks, etc. Europe, Asia, and, in North America, not 

 uncommon in Ohio and also reported from Lancaster Comity, 

 Pennsylvania. Not yet reported from our region. 



