1915] BURLINGAME—ARAUCARIANS 95 
for its entire force depends upon whether these intermediate forms 
are called araucarians or not. It is, of course, precisely the point 
at issue whether these intermediate forms are of araucarian descent 
on the way toward becoming Abietineae or the reverse. In fact, 
if this statement could be substantiated, it would completely 
overthrow the abietinean theory of the descent of araucarians, 
for this theory demands that Abietineans shall have departed in 
many characters, not only toward araucarians, but that this 
departure shall have continued until the latter were actually 
reached. 
In 1909 SINNOTT (57) described from Second Cliff, Massachu- 
setts, another fossil conifer, which he referred to a new genus, 
Paracedroxylon. The pits are uniseriate, remote, and round. 
e rays are without marginal tracheids, and the cells are thin- 
walled and without pits on the ends or horizontal walls. Simple 
pits occur on the radial walls corresponding to the half-bordered 
pits of the adjacent tracheids. Resin canals are normally absent, 
and no sure evidences were found of their traumatic production. 
The new genus, nevertheless, is assigned to the Araucarineae on 
the ground that bars of Sanio are absent. As I shall point out 
later, other anatomists have strongly objected to the reference of 
fossil woods to the Araucarineae on this ground. 
In 1911 JEFFREY described the structure of the cone of Geintizia 
gracillima (41) from the Kreischerville beds. This piece of investi- 
gation furnishes a very interesting application of the canons of 
evidence that have been applied in the attempt to seriate these 
fossil types, for it furnishes an attempt to make a comparative 
study of the structures of the vegetative and reproductive axes 
of the same fossil plant, and to apply to the results the canon of 
vestigial structures. The external appearance of the cones, as well 
as the individual scales, are very reminiscent of certain Taxodineae. 
The branches are thought to be Brachyphyllum. The structure of 
the cone axis is that of SinNot?’s Paracedroxylon (57). From these 
facts the conclusions follow that Paracedroxylon is ancestral to 
Brachyoxylon; that the evolutionary sequence must have been 
Abietineae (Pityoxylon, perhaps), Paracedroxylon, Brachyoxylon, 
Araucarioxylon, modern Araucarineae. It will be pointed out 
