PLATE 13. CORDAITES MATERIARIUM. Tangential section showing the character 

 of the ordinary medullary rays which are sometimes two-seriate, c 40.9 



PLATE 14. DAMMARA AUSTRALIS. Transverse section showing the clearly denned 

 growth ring and its summer wood, and the distribution of resin cells near the 

 medullary rays. X 46.8 



