Fig.' SOI. 



ORGANS OF BEPEODUCTIOK. 37? 



Fig. 802. Fig. 803. Fig. 804. Fig. 805. 



Ftg. 801. Cosdnodon puhinattts. sp. Sporangium enclosed in the calyptra. 



t. Seta or stalk, v. Vaginule. From Henfrey Fig. 802. The Hvgro- 



metric Cord-Moss {Funaria hygrovittrica). f. Perichaetial leaves', p. 

 Stalks or sttce, each ot which supports a sporangium, v, covered by a ca- 

 lyptra. 0. ©.Operculum Fig.%QZ. Sporangium of the Extinguisher- 

 Moss (Encdlypta vulgaris) before dehiscence, v. Sporangium, covered 

 by a transparent calyptra, c, and supported on a seta, s. Beneath the ca- 



lyptra is seen the lid or operculum, o Fig. 804. The sporangium of 



803 after dehiscence. The calyptra and operculum, o, being removed, the 

 peristome, p, may be seen Fig. 805. Pottia truncata. showing the sepa- 

 ration of the operculum from the sporangium. From Henfrey. 



dehiscence of the sporangium the 

 stoma or mouth is entire, smooth 

 or unfurnished with any pro- 

 cesses {fig. 805) ; or it is sur- 

 rounded by one or two fringes 

 of teeth, called the peristome, 

 which are formed from the two 

 inner layers of the wall of the 

 sporangium {fig, 804, p). These 

 teeth are always four or some 

 multiple of that number. Some- 

 times a membrane from the inner 

 wall is stretched across the mouth 

 of the sporangium, and forms 

 what has been called the epi- 

 phragma or tympanum {fig. 806, e). 

 When the mouth is naked, the 

 Mosses in which such a sporan- 

 gium is found are called gymno- 

 stomous or naked-mouthed ; when 



Fig. 806. 



Fig. 807. 



Fig. 806. Sporangium, «, of Hair- 

 Moss deprived of its calyptra and 

 operculum, p. Peristome, e. 



Fpiphragma or tympanum. . 



Fig. 807. Transverse section of a 

 sporangium of Hair-Moss, show- 

 ing the columella surrounded by 

 free spores. 



