564 PROCEEDINGS OF THE AMERICAN ACADEMY, 



primitively persistent in the Araucarian stock and consequently can- 

 not be used as an argument for their antiquity or their affinity with 

 any other group in which the persistence of the foliar strands is a 

 feature of structure in the wood. 



Figure a, Plate 8, illustrates a transverse section of a well preserved 

 Araucarian trunk from the Raritan Cretaceous of Kreischerville, 

 Staten Island, N. Y., which has been descril^ed by the author under 

 the name Araucarioxyloh novehor accuse .'^'^ Through the center of the 

 figure vertically passes the leaf trace. The annual rings are scarcely 

 curved at all, showing that the stem was one of considerable thickness, 

 its age in fact being somewhat over fifty years. This persistence of 

 the leaf trace seems to be a characteristic of all woods of the true 

 Araucarioxylon type and as has been particularly indicated by Dyer *^ 

 and Seward,*^ is likewise a feature of the trunks of the living genera 

 Agathis and Araucaria. Throughout the wood of the figure may 

 be seen numerous dark dots, indicating the position of the true resini- 

 ferous parenchyma, which as has been pointed out in the first article 

 of this series, seems to have been a constant feature of structure in 

 the true Araucarioxyla of the Mesozoic, and which interestingly 

 enough persists as a vestige in the wood of the cone, first annual ring 

 of vigorous branches and the root of the living genera Agathis and 

 Araucaria. Woods of the Araucarioxylon type in the stricter sense, 

 have been described recently by Lignier from the Middle and Upper 

 Jurassic of France.*^ They are exceedingly common in the Cretaceous 

 both of Europe and America. 



In addition to the true Araucarioxylon type, there exist, particu- 

 larly in the Cretaceous, woods in which the pitting and general struc- 

 ture of the tracheids, although unmistakably Araucarian, present 

 certain features of divergence from those properly included under 

 the generic appellation Araucarioxylon. These are pitting not in- 

 variably flattened or alternating and the presence of wound resin 

 canals in connection with injuries. These woods are further char- 

 acterized by rays which are frequently of the Abietineous type 

 after injury. Another interesting feature of these woods is the fact 

 that the leaf-traces, instead of being persistent as is the case with the 

 living genera Agathis and Araucaria, endure only for a very short 



44 Hollick and Jeffrey, Cretaceous Coniferous Remains from Kreischerville, 

 Mem. N. Y. Bot. Garden, 3. 



45 Persistence of Leaf traces in Araucarieae, Ann. Bot. 15, pp. 547 (1901). 



46 Op. cit. 



47 Lignier, V(5g6taux Fossiles de Normandie, IV. Bois Divers, Ire. S6rie, 

 Caen (1907). 



