CONCLUSIONS 
The many new facts in regard to the internal structure of Creta- 
ceous conifers, described in this Memoir as the result of our studies 
of the plant remains from the deposits at Kreischerville, must inevi- 
tably have a more or less important bearing on the question of the 
evolution of the conifers in general and particularly the relationship 
of the Araucarineae to the other tribes of the Coniferales. This 
must follow whether our reference of certain branches and cone 
scales to recognized Cretaceous genera, known previously from 
impressions alone, is accepted or not. Thus, even if it be denied 
that the branches and cone scales we have described as belonging to 
or closely related to the genus Geinitzia are recognized as such or 
not by other students of Cretaceous plants, it nevertheless results 
that a very marked superficial resemblance to a well-defined and 
characteristic sequoiineous type, both in the habit of the leafy twigs 
and in the superficial appearance of the cone scales is entirely illusory, 
since the structure of these remains shows them to be unquestionably 
araucarineous. The conclusion must further be inevitably drawn 
from our observed facts in regard to this extensive Cretaceous conif- 
erous flora, that the superficial appearance of conifers of this period 
is in general of very slight value in determining their actual botanical 
affinities, and that even the reproductive organs, i. e., cones and cone 
scales, of Cretaceous conifers, cannot always be regarded as conclu- 
sive evidence of relationship, since these are externally sometimes as 
deceptive as to their true affinities as are the leafy twigs. 
Unless it be assumed that the Kreischerville flora is entirely unique 
and exceptional, a conclusion quite unwarranted by the nature of 
the impressions associated with the remains with structure preserved, 
its composition and the affinities of the forms represented must be 
of considerable importance from the evolutionary standpoint. It 
may be stated in general that there are present in these beds conifers 
resembling, either in their general habits or in their reproductive 
organs (external features) or in both, the Sequoiineae (Brachyphyl- 
lum, Geinitzia, Eugeinitzia, Pseudogeinitzia, Anomaspis, Sphenas- 
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