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A TEXTBOOK OF THEORETICAL BOTANY 



Fig. 573. — Matonia pectitjota. Transverse section of 

 the stem showing three concentric steles. 



C B A 



Fig. 574. — Matonia pectinata. Polycyclic solenosteie. Drawings from wax 

 models of the stelar system at the node. A, B and C represent different 

 stages in maturity of the structure. {After Tansley and Lulhani.) 



which is termed polycyclic. Thus, as we have seen in Pteridium 

 aquilimim, we have two steles, the inner one of which may be regarded 

 as a solenosteie, and the outer one as a dictyostele (Fig. 572). Since, 



