250 



THE SPORE-PRODUCING ORGANS 

 A 



[CH. 



Fig. 244. Angiopteris cvecta, Hoffm. .-i = pai-t of a young mhik >cfn in surface view from without. 

 j5 = vertical (radial) section of a sporangium such as would be seen on cutting a sporangium (/') in 

 Fig. A, along the line indicated. C= vertical section of an older sporangium showing genetic 

 grouping of cells. Z' = apex of an almost mature sporangium seen from above: such a section as 

 along the line x, x in Fig. E. ^ = vertical section of a sporangium with spore-mother-cells: the 

 tapetum is marked x. /^=transverse section of an almost mature sporangium, b, (5 = annulus; 

 (- = region of dehiscence; a = thin-walled cells which contract. (All x 200.) 



Fig. •245. A=-Corynepleris Essenghi, Andrae, from the Carboniferous 

 (Westphalian). Fragment of a fertile pinna. ( x 6.) B=C.coralloides, 

 Gutbier, from the Westphalian. Fragment of a fertile pinna. ( x 4.) 

 ^' = sorus of the same species seen laterally. ( x 28.) (After Zeiller.) 



