Paiczobotanical Notes. 
THE JURASSIC FLORA OF BORNHOLM. 
39 
D URING the last few years botanists have been gradually, though 
slowly, realising the fact that the study of petrified plants is 
not a purely geological pursuit; but even now the importance of 
Palaeozoic types as evidence bearing on problems of evolution and 
phylogeny receives but half hearted recognition. Slight as it is, 
however, the interest shown by the average botanist in morpho¬ 
logical researches in Palaeozoic botany is much greater than that 
with which he regards the work of those who attempt to interpret 
the imperfect records of Mesozoic floras. It is unfortunate that 
the great majority of plants obtained from rocks of more recent 
date than the Carboniferous and Permian epochs are not preserved 
in such a manner as to retain their internal structure, but to neglect 
post-Palaeozoic fossils for this reason is to adopt a view at once, 
narrow’ and prejudicial to botanical progress. The determination of 
mere casts and impressions is naturally attended with considerable 
risk and offers strong temptation to ill-balanced imagination. It is 
notorious that the custom of applying the generic names of recent 
plants to fossil fragments, which exhibit an external resemblance to 
leaves and shoots of existing species, has not only been responsible 
for entirely false deductions but has brought into deserved 
discredit many contributions to palaeobotanical literature. If on the 
other hand w r e disregard all fragmentary and indecipherable records 
we still find a large amount of material sufficiently well preserved to 
be assigned on substantial evidence to a definite family or generic 
position. It is not too much to expect that a careful examination 
of the remnants of the Mesozoic vegetation will reveal many facts of 
primary importance likely to supply trustworthy information as to 
the geographical distribution during past ages, which may enable us 
to follow the changes that have resulted in the present balance of 
power in the plant world. 
A recently published paper by Hjalmar Moller 1 —a new worker 
in the domain of Paleobotany, trained by Professor Nathorst of 
Stockholm—On the Pteridophytes of Jurassic age from Bornholm, 
is a good example of a careful systematic account of a flora of 
considerable interest. Without discussing certain statements and 
determinations which are open to criticism, it may be of interest 
to draw attention to a few conclusions to be drawn from the 
investigations of Moller, and those previously published by 
1 Bidrag till Rornliolms Fossila Flora. Kongl. Fysiog. Stilish . 
Handl. Bd. XIII. Lund, 1902. 
