14 BOTANICAL GAZETTE [JULY 
primitive group, and that the araucarians have been derived 
from them. 
The first view finds its support in (1) the many close resem- 
blances between the modern araucarians and the paleozoic cordai- 
teans; (2) the apparently greater geological age of the Araucarineae; 
and (3) transitional forms of the Triassic and Cretaceous, which 
appear to become more like the Abietineae from the earliest to the 
later ones. 
The second view does not deny the similarities pointed out as 
supporting the previous view, but in view of other sorts of evidence 
believes them to have been secondarily acquired. It does not 
necessarily deny that they are indications of relationship, but 
merely that they do not indicate direct and immediate relationship. 
. It derives most of its positive support from (a) vestigial structures, 
(b) recapitulation phenomena in seedling and young wood, (c) trau- 
matic responses. 
Since the supporters of the lycopod theory have chosen the 
araucarians as the tribe most favorable to their contention, the 
views of their opponents can be best set forth, perhaps, by marshal- 
ing the evidence that tends to show that the araucarians and, by 
implication, the other conifers have had a direct and immediate 
origin from Cordaitales. 
1. GYMNOSPERMS ARE A MONOPHYLETIC GROUP.—There has been 
a general tendency toward the view that the gymnosperms resemble 
one another so much more closely than they do any other group 
that they must therefore have had a monophyletic origin. This 
point of view was apparently prominent in the minds of more than 
one (45, 52, 77) of the speakers at the Linnaean Society discussion. 
If the monophyletic origin of gymnosperms be admitted, it follows 
almost without dispute that they all have had a filicinean origin. 
Among the known fossil groups of gymnosperms no other can present 
anything like so strong a claim to be the ancestors of the conifers 
as the Cordaitales. Just how numerous, striking, and significant 
are the resemblances between Cordaitales and Coniferales (more 
particularly Araucarineae) can be best shown by a brief review. 
Ever since JEFFREY’S (27, 28, 29) division of vascular plants into 
Lycopsida and Pteropsida on the basis of the presence or absence of 
