148 



ASPLENIOID FERNS 



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Fig. 676. Ceterach officiiiai-iim D.C. Two segments from the upper part of a leaf. The 

 right-hand segment shows the scaly covering of the lower leaf-surface : the left-hand 

 segment the nervation and sori after removal of the scales. The minute indusium is 

 invisible under the low magnification. ( x 8. After Luerssen.) 



Fig. 677. Plejirosottis Pozoi (Lag) Diels ^=a pumary 

 pinna. B^z. secondary pmna, with venation and sori, 

 enlarged. (After Fee, from Natiirl. Pflatizenfam. ) 



