FOSSIL GYMNOSPERMS 151 



CONIFEEALES 



It would be a matter of great interest if the relative an- 

 tiquity of the various groups of Conifers could be determined. 

 The varied structures of this dominant group are extremely 

 perplexing to relate phylogenetically, and some definite histori- 

 cal data would go far toward suggesting the possible sequence. 

 Upon morphological grounds one might be tempted to regard 

 the Taxeae as the most primitive of Conifers, and Abieteae, espe- 

 cially Pinus, as the most highly specialized and recent, but so 

 far as there is any historical testimony it is diametrically 

 opposed to such a view. 



The remains of undoubted Conifers occur from the later 

 Paleozoic (Permian) on, and the total amount of material is 

 enormous. Elaborate studies have sought to determine this 

 material upon the basis of anatomical structure, and the litera- 

 ture of paleobotany is full of names suggestive of aifinities with 

 modern genera, but these methods have proved to be abso- 

 lutely untrustworthy. The sure evidence of well-preserved 

 strobili associated with vegetative structures is lacking, so that 

 the ancient history of this great group is still in a chaotic 

 condition. 



That the phylum is a very ancient one is evidenced by the 

 fact that it is known to have existed during the later periods of 

 the Paleozoic, and possibly earlier, but to what modern group 

 these Permian forms are most nearly allied is absolutely un- 

 known. Their resemblance to the Araucarieae in general vege- 

 tative habit has suggested an Araucarian affinity, but such evi- 

 dence as the strobili furnish contradicts this. 



Leaving these earliest Permian forms of doubtful afiinity, 

 the first suggestion of a modern group is furnished by the extinct 

 genus Voltzia of the Upper Permian and Triassic, which has 

 been referred, apparently on fairly safe evidence, to the Tax- 

 odieae, approaching Cryptotneria in the lobed character of 

 the ovuliferous scale. True Araucarieae and Cupresseae can 

 not be traced with certainty below the Jurassic; Abieteae, 

 allied to Pinus, are not recognized earlier than the Weal- 

 den; while Taxeae have not been discovered lower than the 

 Cretaceous. 

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