BovTyycHIUM DISSECTUM A MUTANT? 53 
caroliniana, has become at some places in Europe); 
for it is not, like S. auwriculata, a tropical species, but. 
one of wide distribution in northern Eurasia where it 
must needs endure winters as severe as ours.—C. A. W. 
Is BorrycHIUM DISSECTUM A STERILE MUTANT OF 
B. optiqguum?—The question in the title, “Is Botry- 
chium dissectum a sterile mutant of B. obliquum,” is 
based on a recent article by C. J. Chamberlain in the 
Botanical Gazette (70: 387) under the title, “Grouping 
and mutation in Botrychium.”? The question is raised 
in the present instance, not with the idea of casting 
doubt on Prof. Chamberlain’s conclusions, but because 
the problem is one to which readers of the FERN JOURNAL 
should be able to contribute additional information. 
Will you not look over the following summary of the 
Chamberlain article for the purpose of comparing its 
data with your own collecting experience or of making 
it the basis of special study in the coming season? We 
shall then be glad to hear reports from as many people 
and places as possible. 
Botrychium is reported as almost invariably growing 
in groups of individuals, not as isolated plants. By 
“oroups” in this case the writer does not mean neces- 
sarily that the plants will be clumped together, but that 
in a patch of thicket where one plant is found, others 
are almost certain to exist. Several such woods groups 
are shown plotted on cross-section paper, in Prof. Cham- 
berlain’s article, with the location of each individual plant 
marked, and with different marks for different species 
of Botrychium. lose 
Of particular importance to the present topic 1s 
another observation, that B. dissectum never occurs 
except in association with B. obliquum, and then always 
in smaller numbers. In four plots, mainly in different 
