170 Rhodora [SEPTEMBER 
sent, in any other group of Conifers except Pinus. The pitting, how- 
ever, is not of the characteristic Araucarian type, and the traumatic 
resin-canals strongly suggest the Abietineae. 
Another character, however, not striking but apparently very im- 
portant, seems to place our wood unquestionably among the Arau- 
carineae. Miss GERRY (7), working in this laboratory, has investi- 
gated the occurrence in the Conifers of bars of Sanio between the 
radial pits of the tracheid wall. She has completely failed to find these 
in either of the living genera Araucaria or Agathis, or in the fossil 
Araucarians such as Araucarioxylon, Araucariopitys and a number of 
forms with the Brachyoxylon type of wood. In all other living genera 
of the Conifers, however, and in a number of closely related fossils, 
including the recently described Prepinus, bars of SANIO were dis- 
covered. In the fossil wood here under investigation, as above 
noticed, they are entirely absent. 
This lignite, therefore, appears to be another addition to that inter- 
esting group of Conifers on the border-line between the Araucarineae 
and the Abietineae, the occurrence of which seems to warrant us in 
believing that the families are related, and that one has probably given 
rise to the other. "The prevalent view at present considers the Arau- 
carineae, largely because of the resemblance of their pitting to that 
of the Cordaites, to be the most primitive Conifers, and the Abietineae, 
from their more complicated structure, to be the most recent members 
of the group. JEFFREY, however, on the testimony presented by the 
very primitive Prepinus, and on the general principle that wounds 
bring about reversions to more ancient structures, as well as on other 
evidence, believes the Abietineae to be the oldest Conifers. ‘The 
traumatic canals of Araucariopitys and of the Brachyoaxylon type, un- 
doubted Araucarians, are explained as relics of a structure normally 
present in their Abietineous ancestors. Perhaps the thickened and 
pitted ray-cells in the traumatic tissue of the lignite here under con- 
sideration may be a reversion to the typical ray of the Abietineae. 
Accepting the correctness of JEFFREY’S views, the phylogenetic po- 
sition of our lignite seems reasonably clear. Its structure approaches 
that of Brachyoxylon more closely than it does that of anything else. 
In its resin-canals, it shows less resemblance to the Alietineae than 
does this fossil, though in its pitting it approaches the Abietineae much 
more closely. Perhaps the most logical explanation of its position is 
to consider it a member of an extinct group of the Araucarineae which 
