1897.] Geology and Paleontology. 611 
was deposited rapidly, The change from the filamentous fossils to the 
well formed Deemonelix is as great, or greater perhaps, than the differ- 
ence between a simple infusorian and a sponge, or as that between a 
simple Spirogyra and a Fucus. No where in the animal kingdom and 
nowhere else in the vegetable kingdom is there to be found paleontolog- 
ical evidence of so rapid a change. 
Yet it must be admitted that, although the rapid change required 
weighs heavily against Barbour’s suggestion, it does not form a con- 
clusive argument. Both animals and plants are known to yield readily 
to surrounding physical conditions, and great and anomalous changes 
are known to occur at a single leap as it were in many of the cases that 
fall under what we commonly call monstrosities. Granting that the 
change indicated by the series that the author thinks he has demon- 
strated is a possible one, there remains the greater and more important 
task of showing the existence at the time that these fossils plants were 
growing of causes adequate to produce it. This done the author’s hy- 
pothesis will be practically unassailable. 
In as much as the plants were aquatic one would not, judging from 
the analogy of aquatic organisms in other instances, expect so rapid a 
change as in the case of land plants. Climatic conditions could doubt- 
less have had but little influence. One is, therefore, left to inquire 
what changes may have occurred in the character and the quantity of the 
salts that the water of the lake held in solution, or of the sediment that 
it carried. As the writer remembers the fossil beds in question there 
is no very apparent evidence of a change in the character of the sedi- 
ment. The beds are not laminated. The structure from bottom to top 
is throughout remarkably and uniformly of the same peculiar mixture 
of fine, indurated, calcareous sand. And it seems, therefore, that, if any 
cause is to be found, it must be looked for in the character or amount 
of the salts tlat were poured into and remained in the lake. As yet 
no one has shown that the silicious material of which the fossils are 
composed is more abundant at one level in the beds than at another, 
and the same may be said of the magnesium, potassium and other salts. 
Evidently there is much work yet to be donein solving this Dæmon- 
elix riddle notwithstanding the great amount of labor that Prof. Bar- 
bour has already expended upon it, and it is to be hoped that he will 
find the necessary time and t for continuing his work both 
in the field and in the laboratory. “Besides an answer to the questions 
implied in the foregoing remarks there are needed answers to other 
questions regarding the structure of the fossil.—F. C. Kenyon. 
