652 MIISCI. (MOSSES.) 



short-pointed from a convex base, and deciduous with the columella attached ; 

 calyptra small, mitriform, 4-5-lobed at the base. (P. sphaericum, Muse. Alle- 

 ghan., No. 196.) Banks of the Ohio Kiver subject to inundation. A minute 

 annual : length of the whole plant 2" - 3". (Tab. 18.) 



3. P. tetragonum, Br. & Sch. Stems gregarious, scarcely 1" high; 

 leaves connivent, ovate-lanceolate, acuminate, the costa ceasing at the apex or 

 excurrent; capsule globose-pyriform. on an erect pedicel (I" high), wide- 

 mouthed when dry ; operculum convex, apiculate ; calyptra very large, twice as 

 long as the capsule, fusiform, 4-sided, splitting on one side. On the ground, 

 San Marcos, Texas, Wright: Vincennes, Indiana, Lesquereux. (Eu.) 



56. APH A IVOR II EG HI A, Sulliv. (Tab. 18.) 



Calyptra small, campanulate-mitriform, lobed at the base. Operculum hemi- 

 spherical, apiculate. Capsule immersed (including the operculum), spherical, 

 nearly sessile, exannulate. Peristome none. Inflorescence monoecious or her- 

 maphrodite : paraphyses globoscly distended at the apex. A genus, by its 

 feeble dehiscence, globose capsule, and the characters of vegetation, forming an 

 intermediate link between Physcomitrella among Cleistocarpous, and Phys- 

 comitrium among Stegocarpous Mosses. (Name from a(pavr)s, unapparent, 

 and pJ/y/Aflj rupture, or suture; i. e. dehiscence obscure.) 



1. A. serrata, Sulliv. Stems 2" -3" high, simple or innovating from 

 below the apex ; leaves oblong-lanceolate, serrate, costate nearly to the point of 

 a large and loose hexagonal areolation; capsule (when mature) separating under 

 pressure along an indistinct transverse suture (not visible at an early stage) into 

 two equal portions; antheridia ^occasionally intermixed with a few archegonia) 

 in the axils of the perichastial leaves, usually naked, sometimes with 1 or 2 

 small perigonial leaves. (Sulliv. in Mem. Amer. Acad., n. ser. 4, p. 60, t. 2.) 

 Damp soil, New England to Ohio. Strikingly like Physcomitrella patens; 

 distinguished mainly by its feeble operculation, and the denser texture of the 

 outer wall of the capsule. (Tab. 18.) 



TRIBE XXIII. SPLACHNE^. 



57. SPL.ACII NUM, L., Br. & Sch. UMBRELLA-MOSS. (Tab. 18.) 



Calyptra small, conic, entire or uneven at the base : operculum convex or 

 mammillate. Capsule erect, obovate-oblong or subcylindrical, with a very large 

 spongy and differently colored obovate, globose or umbraculiform apophysis, 

 long-pedicellate. Peristome single, of 16 double teeth in pairs, reflcxed when 

 dry. Columella emergent, capitate. Inflorescence mostly dioscious : male 

 flower capituliform, terminal. Plants of a peculiar structure, readily recog- 

 nized by the exceedingly large apophysis of the capsule ; perennial, csespitose, 

 growing only on the dung of herbivorous animals ; stems innovating from below 

 the floral apex, dichotomous, of a succulent soft texture ; leaves lanceolate, 

 taper-pointed, thin and delicate, with large loose, oblong, hexagonal areolas ; 

 costa slight, ceasing below the point. (S,ir\ay\vov, a name used by Dioscorides 

 for some cryptogamous plant.) 



