39 



B. Capsule not pedicellate, without neck. Spores 

 very large, 0,i— 0,a mm. Prothallium not persistent. 



162. Archidium. Capsule globose; columella wan- 

 ting. Calyptra rudimentary or irregularly splitting. Leaves 

 often distant. 



II. Ephemerece. Stem wanting or indistinct. Leaves 

 often nerveless, smooth or (seldom) papillose-spinulose. 

 Capsule globose without neck, immersed. Prothallium 

 persistent. Plants minute. 



A. Leaves smooth. 



163. Ephemerum. Capsule not or indistinctly pedi- 

 cellate; columella rudimentary or complete, more or less 

 fugacious. Calyptra campanulate or (in one species) sub- 

 cucullate. Leaves often nerveless. Spores 0,o2— O.os mm. 

 Prothallium abundant. Dioecious. 



164. Nanomitrium. Capsule not pedicellate, colu- 

 mella wanting. Calyptra campanulate-mitriform, very small. 

 Leaves nerveless. Spores about 0,o3 mm. Prothallium 

 not abundant. Paroecious. 



B. Leaves papillose-spinulose on both sides and on 

 the costa. 



165. Ephemeridium (new genus). Capsule indi- 

 stinctly pedicellate ; columella wanting. Calyptra campanu- 

 late, somewhat large. Spores 0,o2 mm or larger. Pro- 

 thallium not abundant. Dioecious. 



Fam. 36. VoitiacesB. 



166. Voitia. Capsule ovaloblong or globose. 



Fam. 37. Physcomitrellacese. 



167. Physcomitrella. Capsule subglobose, irregu- 

 larly splitting. Calyptra split or faintly crenulate at base, 

 scarcely covering the point of the capsule. 



168. Aphanorhegma. Capsule globose or oval, 

 regularly and horizontally splitting. Calyptra lobulate, 

 covering more than the point of the capsule. 



