g2 BOTANICAL GAZETTE [AuGUST — 
The scales and leaves resemble those of the hard pines, while the 
presence of abundant tangential pitting of the autumn wood is a 
character of soft pines. The ray cells are highly resinous, and there 
are no ray tracheids such as are characteristic of the Pineae. 
The authors point out that these are just the characters shown by 
the wood of the cones of hard pines. They enforce their argument 
from vestigial structures in the following words: ‘‘there can be little 
doubt that in the wood of the cones of Pinus palustris, for example, 
the general absence of marginal tracheids, the highly resinous char- 
acter of the rays, and the abundant presence of tangential autumnal 
pits, all features of difference from the vegetative wood structure of 
existing hard pines, are ancestral characters, since such characters 
are apt to linger on in the reproductive axes. In no other way 
can the presence of these features in the wood of the cone be 
explained.’”’ They call attention to the great geological age of the 
pines as further support of the application of these principles. 
‘“‘There is good reason to believe from recent researches (33) that 
the genus Pinus in essentially its modern form, so far as the external 
features of the female cones go, existed as far back as the Jurassic. 
There is even evidence that the two great series of the hard and 
soft pines existed at this early period, so that the geological exten-_ 
sion of the genus must have been much more remote.” 
Following up the same line of reasoning, JEFFREY (34), in 
a paper on wound reactions of Brachyphyllum, put forward the 
suggestion that ‘‘there is nothing inherently improbable in the 
derivation of the Araucarineae from an abietineous stock.” He 
puts forward three sorts of evidence in support of this suggestion. 
In the first place, he points out, the wound reactions of Brachy- 
phyllum are of exactly the same character as those of Sequoia. Ina 
previous investigation he was led to conclude, from the traumatic 
production of resin canals, taken in conjunction with their vestigial 
occurrence in the cone axis, first annual ring of the stem, and in the 
root, that resin canals were characteristic of the ancestors of 
Sequoia (30) as well as of Abies and certain other Abietineae (31). 
By combining the vestigial structures exhibited by the cones of the 
living araucarians with the wound reactions of Brachyphyllum, 
he is led to infer a similar ancestry for Araucarineae. 
