466 BOTANICAL GAZETTE [june 



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 27:243-255. 1913. 



7. Jeffrey, E. C., The history, comparative anatomy, and evolution of the 

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Bot. (Pringsheim) 9:50-126. 1873-74. 



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EXPLANATION OF PLATES XIII-XV 



PLATE XIII 



Fig. I. — Magnolia acuminata Linn.: pitting in facet of small vessel seg- 

 ment, showing scalariform primary pit areas and isolated circular bordered pits; 

 X300. 



Fig. 2. — Todea hymenophylloides A. Rich.: pitting in lateral facet of 

 tracheid, showing typical scalariform and transitional types of pitting; X300. 



Fig. 3. — Magnolia acuminata: scalariform pitting in lateral facet of 

 vessel segment ; X400. 



Fig. 4. — Magnolia acuminata: pitting in lateral facet of vessel segment, 

 showing scalariform and transitional types of pitting; X450- 



Fig. •,.— Pinus Strobus Linn.: tangential longitudinal section, showing 

 knotenformige thickenings of middle lamella; X500. 



Fig. 6. — Todea hymenophylloides: pitting in lateral facet of tracheid, 

 showing pairs of elongated bordering areas superimposed over single scalariform 



