Vol. 43 No. 5 
BULLETIN 
OF THE 
TORREY BOTANICAL CLUB 
The origin of new varieties of Nephrolepis by orthogenetic saltation 
|, Progressive variations 
R. C, BENEDICT 
(WITH PLATES 10~15) 
A. INTRODUCTION 
’ 1. Definition and scope of paper 
The title, ‘‘ The origin of new varieties in Nephrolepis by ortho- 
genetic saltation,” was selected to emphasize two points: first, 
that the variations to be described are discontinuous and of con- 
siderable magnitude, i.e. jumps or saltations; second, that these 
variations occur in definite series along a few limited lines, 1c. 
they are orthogenetic. I purposely beg the question as to whether 
they are mutations or not because I do not know. The exact 
application of the term, mutation, seems at present to be in a 
state of some uncertainty, and in any event, there may be con- 
siderable question about classifying these vegetative fern sports 
in the same category with the forms of Oenothera, among which, 
surely, orthodox mutations must exist. 
Nephrolepis is a genus of tropical ferns, several species of 
which have been cultivated. Nearly all these species have 
shown some variation under cultivation, but one of them, J. 
exaltata, through its variety, the so-called “Boston fern,” NV. exaltata 
bostoniensis, has been especially prolific of new forms. From this 
variety there have arisen in about fifteen years at least sixty 
[The Buiietin for April (43: 169-206. pl. 7-9) was issued May 20, 1916.] 
207 
