74 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 
here is found true centripetal wood and a general organization of 
the transfusion tissues, similar to that present in certain Cordaitales. 
On the basis of the lines of argument derived from a consideration 
of the structure of the wood and of its wound reactions in Brachy- 
oxylon and .1raucariopitys; of the structure of the ovuliferous cone 
scales of recent and Cretaceous Araucarineae and of the archigymno- 
spermic type of leaf-bundle found in Cretaceous pines, and pre- 
eminently in Prepinus, we conclude that the type of araucarian charac- 
teristic of the Kreischerville flora is more ancient in its affinities than 
the araucarineous stock represented by the living 4 gathis and Ягаи- 
caria, and was clearly derived from abietineous ancestry and particu- 
larly from forms closely allied to the living genus Pinus. 
It will probably be urged by advocates of the araucarineous origin 
of the Coniferales that the comparatively slight representation of the 
abietineous stock in the Mesozoic is against their having been the 
progenitors of the modern groups of Coniferales. That the Abieti- 
neae were really scantily present in the Mesozoic flora is, however, 
open to question. In the Kreischerville deposits we have found 
remains of at least seven distinct species of Pinus and one species of 
Prepinus. It would be difficult at the present epoch to gather the 
water-borne relics of seven species of Pinus in the same resting place, 
except, perhaps, in a stream issuing from the pinetum of a botanical 
garden, and this in spite of the fact that there are some ninety species 
of the genus now in existence. There is accordingly no good reason 
to suppose that Pinus was not quite as well represented by species in 
the middle Cretaceous as it is at present. Even if we admit that the 
Abietineae were less numerous in the Mesozoic than at present, it 
appears to be a fallacious conclusion that on that account they were 
necessarily less primitive than the apparently more prevalent Arau- 
carineae. It would not be less reasonable to suppose that the richly 
branched and leafy crown of a tree is its oldest portion. It is highly 
probable in view of the various facts described in this Memoir that 
the Araucarineae actually did represent the abundant crown of the 
coniferous genealogical tree in Mesozoic time, but that by their 
almost complete extinction in the important changes which ushered in 
the Tertiary period, a lower, more ancient and overshadowed 
branch, the Abietineae, became a new “ leader ” and in its subsequent 
development very much obscured the original plan of phylogenetic 
development. The validity of this conclusion will be strengthened 
when certain experimental results, obtained by one of us in the case 
