470 INTRODUCTION TO CEYPTOGAMIC BOTANY. 



I. SCHISTOCARPI, Mont. 

 M'usci scHiSTOCAapi, Brid. 



1. Ande^ace^S!, Lindl. 



Sporangium sessile on the elongated receptacle, split into 

 fotir or more valves, which are either connected above by the 

 operculum or are perfectly free. Elaters, none. 



619. In external characters this tribe bears a close resem- 

 blance to Jungermannice, and there is even some resemblance 

 to what is called the dotted leaves of certain of that race of 

 Hepaticw (Fig. 99, /) ; but the cells are not connected together 

 by tubes in the thick walls, nor are the leaves disposed after 

 the same fashion ; besides which, there is a distinct columella^ 

 They are, in fact, as decided mosses as any, in spite of their 



Fig. 101. 



Sporangium of Aoroschisma Wilsoni, from Hookerian Herbarium, 

 Magnified. 



valvate sporangia. In most species the valves adhere to the 

 operculum, but in Andrcea Heinemanni they are free. This 

 species is, moreover, remarkable for the apophysis or swelling 

 at the base of the sporangium. In this genus, as in Sphag- 

 num, the stem is elongated, forming a sort of filiform recep- 

 tacle to the vaginula, so that the sporangium, though really 

 sessile, appears as if it were pedunculate. The calyptra, more- 

 over, bursts irregularly, though it is somewhat mitriform. 



