In diversity of form, size, growth characteristics — in other 
words— in criteria which are used to separate species of the wilds, 
these new forms have exceeded the limits of variations among 
the wild species of Nefi/n olep/s , the leaves of all of which are only 
once divided, and often hard to differentiate. Recently there have 
come to my attention forms of the Boston fern series in which 
the leaves reproduce new plants, besides forms with corkscrew 
twists in the leaves, and also forms showing other types of varia- 
tion extraordinary tor this genus. 
The multiplicity of different types of variation is interesting, 
but even more so is the fact that alongthe main lines of variation, 
leaf division, dwarfing, and ruffling of leaves, there have appeared 
such consecutive series, in which each of these characters has 
been intensified. Such series of variation are called orthogeneti i\ 
and there is a growing belief among students of evolution that 
orthogenesis, so called, or in other words, evolution in a definite 
direction, must be accepted to account for many of the phenomena 
of variation evident, both in fossil forms and in present day 
groups of species. (See Chart, page 7.) 
Both as regards orthogenesis, and as regards the presentment 
of definite new forms, recently evolved, the Boston fern offers 
evidence without precedent among other groups of plants and 
animals. The ultimate status of these new ferns as “species” 
must be left open for further study. 
R. C. Benedict. 
An exhibition of about seventy-five varieties of the Boston fern has recently 
been installed in House No. 10 of the conservatories of the Brooklyn Botanic 
Garden. This is practically the same collection as the one displayed by the 
Garden last fall at the exhibition of the Massachusetts Horticultural Society in 
Boston, where the officers of the Horticultural Society created a special prize 
and awarded a trold medal to the Brooklyn Botanic Garden on account of the 
unusual excellence of the collection.— Ed. 
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