MOSSES, 



C 513 ] 



MOSSES. 



escape by its decay (ASTOMUM, fig. 60). 

 In the ANDIL?EACE.E (fig. 11, p. 41) the 

 sporange bursts by vertical slits, so as to 



Fisr. 476. 



Fig. 477. 



Fig. 476. Coscinodon pulvinatus. Fragment of peri- 



stome. Magn. 100 diams. 

 Fig. 477. Barbula flavipes. Fragment of peristome. 



Magn. 100 diams. 



be divided into valves, as in the Junger- 

 manniese, and there is no column in the 

 sporange here j but the valves do not sepa- 

 rate at their summits, and the character of 

 the leafy stem at once distinguishes these 



Fig, 478. 



Fig. 479. 



Fig. 478. Phascum serratum. Sessile sporange enclosed 

 by few leaves. Magn. 15 diams. 



Fig. 479. Pottia trtmcata. Operculnm separating from 

 the sporange. Magn. 10 diams. 



Mosses from the Hepaticse. The ordinary 

 ccur.se, however, in the Mosses is the forma- 

 tion of a horizontal slit near the top of the 



sporange, so that the upper part falls off like 

 a lid (operculum, fig. 479). 



The sporange of the Mosses exhibits a 

 very complex anatomical structure, which 

 we have not space to enter into very mi- 

 nutely : it will suffice to state that the 

 lower part next the peduncle is sometimes 

 enlarged into a thickened mass, called the 

 apophysis ; sometimes the peduncle is veiy 

 long, sometimes very short (Phascum, fig. 

 478), so that the sporange is hidden in the 

 perichsete ; finally, the mouth may either 

 exhibit a smooth edge (fig. 479), or a single 



Fig. 480. 



Cinclidium arcticum 



Part of double peristome, the inner processes united 

 into a plaited membrane in the centre. 



Magnified 100 diameters. . ... 



(figs. 476, 477) or double (figs. 483 ; 484) 

 fringe of veiy variously constructed teeth, 

 which are of great service in discriminating 

 the genera. When the mouth of the spo- 

 range is naked, the Mosses are called gym- 

 nostomom, when furnished with only a 

 single row of teeth haploperistomous. When 

 a double peristome exists, the outer con- 

 sists of teeth, the inner of processes or cilia 

 (fig. 483) or of both (E-rt/um). The teeth 

 sometimes arise directly from the mouth of 

 the sporange, sometimes are seated on a 

 basal membrane, sometimes connected to- 

 gether irregularly (FUNAKIA, fig. 259, p. 

 342), or by regular bars (GUEMBELIA, fig. 

 291, p. 366), or the whole of the inner circle 

 may be conjoined entirely (BUXBAUMIA, 

 iig. 93, p. 126) or at the tips (fig. 480) into 

 a membrane, or by a number of cross bars 

 into an open trellis (fig. 484). . The. outer 

 rows of teeth are continuations of the inner 

 layers of tissue of the sporange (fig. 481) ; 



2L 



