196 BRYACE^. [Pyramidula. 



70. PYRAMIDULA, Brid. 



Calyptra large, enclosing the capsule, dehiscent by a lateral 

 cleft. Orifice of the capsule naked. Sj^ores very large, smooth. 



1. P. tetragona, Brid. Stems short, simple : leaves ovate- 

 oblong, gradually acuminate or cuspidate by the excurrent 

 costa, concave and entire : male buds at the base of the fertile 

 plants : capsule globose, short-pedicellate, Avith inflated collum ; 

 lid convex, obtusely apiculate. — Muse, Recent. Suppl. iv. 20. 

 .Physcomitrhim tetragonum, Bruch & Schimj). Bryol. Eui\ 

 t. 298; Sulliv. Mosses of U. States, 52. 



Hab. Sandy soil, San Marcos, Texas (Wricjht)\ sandy plain near the 

 depot atVincennes, Indiana (Lesquereux) ; plains of Colorado (E. Hall). 



71. APHANORHEGMA, Sulliv. (PL 4.) 

 Plants gregarious or subcespitose, whitish green. Stems 

 short, sparingly dividing by innovations. Flowers monoecious 

 or occasionally syncecious. Calyptra narrowly conical, mitri- 

 form, covering the upper part of the capsule by its lobate base. 

 Capsule immersed, very shortly pedicellate, splitting in the mid- 

 dle at maturity, without decoloration at the line of separation. 



1. A. serratum, Sulliv. Lower leaves open, flexuous, the 

 upper close, nearly erect, oblong and spatulate-lanceolate, short- 

 acuminate, serrate from the middle upward ; costa percurrent ; 

 basilar cells large, rectangular, the marginal often yellowish : 

 capsule globose, minutely pajiillose at the apex : spores tuber- 

 culate. — Mosses of U. States, 52, t. 4, and Icon, Muse, 95, 

 t. 57. Schistidium serratum, Hook. & Wils, in Drumm, Muse. 

 Am. n. 20 ; Sulliv, Mem, Amer, Acad, n, s. iii. 60, t. 2, C. 

 PJiyscomitrium serratum, Muell, Syn, ii. 545, 



Hab, Damp clayey ground, river-banks, road-sides in the woods, and 

 in open cultivated ground in the Northern and Middle States; not rare. 



72. PHYSCOMITRIUM, Brid, (PI. 4.) 



Plants simple or sparingly branching at base by innovations, 



Calyptra scarcely descending to the middle of the capsule. 



Capsule regularly dehiscent with a distinct naked orifice. 



1. P. immersum, Sulliv. Plants small, annual, gregarious 

 or widely subcespitose, green : leaves large, obovate or lingu- 



