FERNS, FOSSILS AND FUEL 
was a tiny woody cylinder, reminding us of certain pterido- 
phytes, while the spore-capsules were similar to those of 
mosses. Early impressions of this kind of plant had 
been found in other Devonian localities and had been 
assigned to the genus Psilophyton, and the newly discov¬ 
ered structural material was therefore given the name 
psilophytales. One of the genera got the name Rhynia 
from the place where it was found. 
It seems that the psilophytales had sprung from highly 
organized algae, and that some important features of 
structural difference had already been acquired during 
their marine life. This high algal type left no traces. 
The exact place of the psilophytales in the biologic sys¬ 
tem of plants is uncertain. They do not show a dis¬ 
tinct affinity to any of the great subdivisions of living 
plants. Some botanists have emphasized their similarity 
to mosses, while others have laid great weight on features 
that are similar to the pteridophytes. Perhaps other strik¬ 
ing discoveries may some day be made which will widen 
our knowledge of early Devonian plant structure and 
will clear up the uncertainties. Until that happens, it 
will be impossible to make a complete picture of the early 
Devonian landscape, nor will it be feasible to assign a 
definite place in the biological system of plant life to 
the psilophytales. 
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