540 PROCEEDINGS OF THE AMERICAN ACADEMY. 



4. Certain woods from the Jurassic and Lower Cretaceous, pos- 

 sessing at once araucarian pitting, of the tracheids, abundantly devel- 

 oped wood parenchyma and strongly pitted medullary rays are in 

 reality aruacarian in their affinities and not abietineous as has recently 

 been asserted by Gothan on the insufficient basis of their ray structure. 



5. The characteristic features of Mesozoic araucarian woods are 

 retained to a large degree in the wood of cone axis, root and first 

 annual ring of vigorous branches of living representatives of the Arau- 

 cariineae. 



6. They may be recalled by experimental means particularly in 

 the root and the seedling stem. 



