212 The Ohio Naturalist. [Vol. XIV, No. 2, 



1. Sporophyte borne on a pseudopodium developed by 

 the gametophyte ; columella not extending through 

 the spore cavity; sporangium without air ca\'ities; 

 without or with a calyptra. 



a. Gray-green bog-mosses with two kinds of cells 



in the gametophyte; sporangium opening 

 by a lid; archegonium breaking irregularly 

 at the tip. Sphagne^, Bog-mosses. 



Sphagnales, Sphagnaecce, Sphagnum. 



b. Dark green rock mosses, not with two kinds of 



cells; sporangium opening by four or more 

 vertical slits; archegonium developing a 

 calyptra. Andre.e^, Granite Mosses, 



Andreaeales, Andreaeaceae, Andre^a. 



2. Sporophyte not borne on a pseudopodium, usually with a 



prominent stalk or seta ; columella usually extending thru 



the spore cavity ; sporangium with an air cavity, usually 



with stomata; archegonium developing a calyptra. 



Musci, True Mosses. 



B. Archegonia having their venters imbedded in the thallus; 

 gametopyhte thalloid, without typical scales; its cells 

 usually with only one or two chloroplasts ; sporophyte 

 with intercallary growth between the foot and the 

 sporangium; sporangium with a central columella, open- 

 ing by two valves, sometimes with stomata. 

 Anthocerote.e, Hornworts, Antocerotales, 

 Anthocerotaceae, Notothylas, Anthoceros, Dendroceros. 



SYNOPSIS OF THE HEPATIC^. 



I. Gametophyte a thalloid, dorsi ventral frond composed of 

 several distinct tissue layers; mostly with air passages; 

 sporophyte spherical or with a foot and short stalk; 

 sporangium rarely opening by 4-S valves. 



Marchantiales 



1. Sporophyte spherical, without foot or stalk, remaining 



enclosed in the venter of the archegonium ; no sterile 

 cells in the sporangium. Ricciace^, Riccia, 



Ricciocarpus, etc. 



2. Sporophyte differentiated into foot, stalk and sporan- 



gium, breaking thru the venter of the archegonium 

 at maturity; sporangium with spores and sterile 

 cells which mostly develop as elaters. 

 Marchantiacca^, Targionia, Grimaldia, Conocephalus 



Lunularia, Marchantia, etc. 



