220 



MOSSES AND FERNS 



CHAP. 



The sporogonium of Tetraphis has a peristome of pecuHar 

 structure, and not strictly comparable to that of any of the 

 other Mosses. After the operculum falls off the tissue lying 

 beneath splits into four pointed teeth, which, however, are not, 

 as in Funaria, composed simply of the cell walls, but are masses 

 of tissue. 



All the other higher Bryales, with the exception of the 

 Polytrichacese, have the peristome of essentially the same struc- 

 ture as that described for Funaria. Sometimes the teeth do not 

 separate but remain as a continuous membrane, e. g., the inner 



Fig. 119. — ^A, Barbuta fallax, upper part of the capsule, showing the slender twisted 

 peristome teeth X about 20. B, Fontiuatis antipyretica, showing double 

 peristome (after Schimper). C, Polytrichum commune, peristome and epiphragma 

 X8. D, P. commune, ripe capsule; i, with, z, without the calyptra.XS* 



peristome of Buxhaumia, or a perforated membrane, as in Fon- 

 tinalis (Fig. 119, B). 



The base of the capsule, or apophysis, which Haberlandt 

 (4) has shown to be the principal assimilative part of the sporo- 

 gonium, and which alone is provided with stomata, sometimes 

 becomes very large, and in the genus Splachnum (Vaizy (i)) 

 especially forms a largely-developed expanded body, which 

 must be looked upon as a specially-developed assimilating ap- 

 paratus. 



