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foliage slioots. Professor Jeffrey of Harvard has re- 

 cently given an account of a new type of stem 

 (Woodworthia) from the petrified Triassic forest of 

 Arizona possessing some Araucarian characters, 

 though differing from existing species of Araucaria 

 in certain structural features, a combination of 

 characters regarded by this Author as an indication 

 of relationship with the family of Conifers, which 

 includes the Pines, Firs, Larches and other well-known 

 northern genera. 



It is, however, from the records of Jurassic rocks 

 that we obtain the most satisfactory information as to 

 the great antiquity and the very wide geographical 

 range of the ancestors of the recent genus. The plant- 

 beds of the Yorkshire coast afford clear evidence of 

 the occurrence of Araucarian trees in the woodlands 

 of the Jurassic period. Petrified wood has been found 

 at Whitby, associated with jet, showing the minute 

 structural characteristics of the surviving species of 

 Araucarieae, and it is not improbable that some at 

 least of the Whitby jet has been formed from the wood 

 of Araucarian plants. The carbonised remains of 

 leafy shoots preserved in the Jurassic shales near 

 Scarborough and on other parts of the Yorkshire 

 coast include twigs hardly distinguishable from those 

 of Araucaria excelsa, though the resemblance of 

 external form alone, especially in the case of foliage 

 shoots, does not amount to proof of generic identity. 



