CH. XLVIIl] ABIETINEAE 369 



bulk largely in Mesozoic floras before the closing stages of the 

 Jurassic period and more especially in the earlier days of the 

 Cretaceous era. The abundance of Abietineous cones in Lower 

 Cretaceous strata, a period later than that in which the Arau- 

 carineae are abundantly preserved in plant-bearing deposits, at 

 least points to a later maximum development of the Abietineae, 

 and such data as we have seem to favour a northern rather than 

 a southern origin. Winged seeds, hardly distinguishable from those 

 of modern Pines (fig. 788, p. 396), from Rhaetic beds in the South of 

 Sweden,, foliage-shoots from beds of the same age exhibiting features 

 now associated with the Abietineae, demand serious consideration 

 in connexion with the antiquity of the family, though it can hardly 

 be maintained that they furnish proof of the existence in Rhaetic 

 and Liassic floras of true Abietineae. The occurrence of a winged 

 pollen-grain (fig. 491, G; Vol. in. p. 298) in the partially decayed 

 wood of Antarcticoxylon might be urged as a plea for a southern 

 origin of the family, but an extended bladder-like exine is not a 

 monopoly of the microspores of the Abietineae. 



The following types selected in illustration of the fossil records 

 of the Abietineae show how difficult it is in many cases to deter- 

 mine the precise position within the family to which cones or 

 foliage-shoots should be assigned. Palaeobotanical literature con- 

 tains many species referred to Abies or Abietites, Cedrus, and other 

 genera, but it is usually impossible from the available data to carry 

 identification so far. A few examples may be quoted: certain Lower 

 Cretaceous cones bear a very close resemblance to those of Cedrus 1 , 

 but an examination of some of the less familiar cones of existing 

 species of Abies and Picea shows that the reasons for connecting the 

 fossils with Cedrus are not entirely satisfactory. The fossil wood 

 described under Cedroxylon does not denote that the parent-plants 

 were more closely allied to Cedrus than to some other genera of the 

 same family. Boulay 2 has described some seeds from Miocene beds 

 in France as Cedrus vivariensis which he unhesitatingly regards as 

 generically identical with those of recent Cedars, and there is no 

 reason to doubt the correctness of this conclusion. Cone-scales 

 bearing two seeds from Miocene beds in Spitzbergen described by 



1 See page 385. 



2 Boulay (87) p. 235. 



S. IV 24 



