GiOSSOrTERIS. 



41 



of Glosxopteris. Associated with these scale-fronds it was noticed 

 that groups of minute bodies, almost invisible to the naked eye, 

 frequently occurred. On microscopic examination it was discovered 

 that these bodies were sac like structures of peculiar form, 

 often beautifully preserved, although not unfortunately in the 

 petrified state. A few further specimens have since been found 

 in the collections at Cambridge, and on this material it has been 

 possible to show that, in all probability, these sac-like organs are 

 the sporangia of Glussopteris Browniana. 



- mh 



II 





Fig. 12. — Sporangium-like organs of Glosxopteris Browniana, Broiig. 

 V. 7202. X 30. 



These organs occur in gi'oups, which suggest a comparison with 

 the sori of ferns. They are somewhat elliptical in shape, tapering 

 at either extremity (Text- figs. 12 and 13). They measure 

 l'2-l'5mm. along the major, and •6--8mm. along the minor axis. 



In many examples one end of the sac-like body is prolonged into 

 a short, bent neck ; the whole organ having thus the appearance 

 of a retort. The cell-walls of the outer layer of the sac are 

 extremely characteristic, the cells being rhombic in shape, and 

 much longer than broad (Text-fig. 13). The cell-walls of the 

 inner layer are much less conspicuous (Text-fig. 14). 



