652 (52) 3IUSCI. (mosses.) 



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

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

 ghan., No. 196.) — Banks of the Ohio Eiver subject to immdation. — A minute 

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



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

 leayes connivent, orate-lanceolate, acimiinate, the costa ceasing at the apex or 

 excuiTcnt; capsule globose-pp-iform, on an erect pedicel (1" high), ■wide- 

 mouthed when dry ; operculum conyex, apiculate ; calypti'a reiy large, twice as 

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

 San Mai'cos, Texas, Wright: Vincennes, Indiana, Zes^'iiereua:. (Eu.) 



56. APHAIVORHEOMA, Sulliv. (Tab. IV.) 



Calyptra small, campanulate-mitiifonn, lobed at the base. Operculimi hemi- 

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

 nem-ly sessile, exannulate. Peristome none. Inflorescence monoecious or her- 

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

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

 intermediate link between Physcomitrella among Cleistocarpous, and Phys- 

 comitrium among Stegocarpous Mosses. (Name from dcpavTjs, unapparent, 

 and prjyfia, 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, sen-ate, costate nearly to the point of 

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

 pressure along an indistinct transverse sutui-e (not visible at an early stage) into 

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

 in the axils of the perichsetial 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. — Stiikingly like Physcomitrella patens; 

 distinguished mainly by its feeble operculation, and the. denser textm'e of the 

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



Tribe XXm. SPLACHNE^. 



57. SPL.ACHNU1TI, L.,Br.&Sch. Umbrella-Moss. (Tab.IV.) 



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

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

 spongy and difi'erently colored obovate, globose or umbraculiform apophysis, 

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

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

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

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

 gi'owing 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 areolije ; 

 costa slight, ceasing below the point. {^TrXdyxvov, a name used by Dioscorides 

 for some cryptogamous plant.) 



