CONIFERALES (PINACEAE) 305 



of the existence of that tribe before the end of the Cretaceous. Until 

 recently, the oldest claim made for Sequoia was its occurrence in the 

 Wealden (lowest Cretaceous) of Portugal; but Zeiller and Fliche 

 (82, 88) have announced cones of Sequoia from the Jurassic of France, 

 which represent both the S. gigantea and the S. sempervirens types, 

 and therefore the genus was already differentiated in the Mesozoic. 

 Much doubt has been thrown upon these determinations by increasing 

 knowledge in reference to the extensive araucarian flora of the Meso- 

 zoic, for cretaceous forms referred to Sequoia have proved to be arau- 

 carian. Of still greater uncertainty is Voltzia of the Upper Permian 

 and Triassic (61), which has been referred to the Taxodineae on the 

 evidence of certain vegetative and cone characters, the cone scales 

 being said to be two-lobed as in Cryptomeria. With the triassic 

 Voltzia and the Jurassic Sequoia in a state of uncertainty, the only 

 safe conclusion is that Taxodineae are not older than the Cretaceous 

 and that the most certain remains are those of the Tertiary. 



The same statement may be made for Cupressineae, for although 

 Cupressus-like twigs and cones have been described from the Jurassic, 

 there is no reliable evidence of the tribe earlier than the Upper 

 Cretaceous. 



It is clear, therefore, that the Abietineae are much older than the 

 Taxodineae and Cupressineae, and this historical relation favors the 

 view that these two tribes have come from abietineous stock. 



The Araucarineae are rival claimants with the Abietineae for 

 antiquity, and the question as to the relationship of these two tribes 

 is of great interest. It is now known that there existed an extensive 

 araucarian flora during the Mesozoic, and that this was probably 

 the dominant type of Coniferales at that time. Araucarians ranged 

 from Greenland to Patagonia in one hemisphere, and from Spitz- 

 bergen to Cape Colony in the other, but apparently became almost 

 extinct at the opening of the Tertiary, and are now restricted to South 

 America and the Australasian region, having disappeared from 

 North America, Europe, Africa, and practically all of Asia (118, 137). 

 In our own country the Atlantic coastal plain evidently supported 

 during the Mesozoic an abundant araucarian vegetation, and from 

 the cretaceous clay pits of Staten Island alone, Hollick and Jeffrey 

 have described recently (155) nine new genera and recognized seven 



