II MUSCINE.-E—HEPA TIC.-E—MA RCHA NTIA CEAL 2 1 



Classification of the Hepatic^ 



The Hepaticae arc readily separated into the three following 

 well-marked groups. 



Group I. Marchantiaceae. 

 Group II. Jungermanniaceae. 

 Group III. Anthoceroteae. 



The following diagnoses are taken, with some modifications, 

 from Schiffner.^ 



Group I. Marchantiace.-e 



Gametophyte always strictly thallose, composed of several 

 distinct layers of tissue, the uppermost or chlorophyll-bearing 

 cells usually containing large air-spaces. The dorsal epidermis 

 usually provided with pores, ventral surface with scales arranged 

 in one or two longitudinal rows. Rhizoids of two kinds, with 

 smooth walls, and papillate ; sexual organs, except in the lowest 

 forms, united in groups which are often borne on special stalked 

 receptacles. The first divisions of the embryo are arranged like 

 the quadrants of a sphere. Sporogonium either with or without 

 a stalk, and all the inner cells forming spores, or some of them 

 producing elaters. No columella present. 



Fani. I. RicciacecB 



Chlorophyll-bearing tissue with or without air-chambers, 

 and, where these are present, they never contain a special 

 assimilative tissue. Epidermal pores wanting or rudimentary. 

 Sexual organs immersed in open cavities upon the dorsal 

 surface. Sporogonium without foot or stalk, and remaining 

 permanently within the venter of the archegonium. All the 

 cells of the archesporium producing spores. 



Fain. 2. CorsiniecE 



Air-chambers well developed ; epidermis with distinct 

 pores ; sexual organs in distinct groups, but the receptacles 



1 Schiffner (i), p. 5. 



