30 Rhodora [FEBRUARY 
found in either of these insular areas, it is not probable that the some- 
what intermediate plant which simulates Æ. palustre but has the tech- 
nical characteristics of Æ. densum can be treated as of hybrid origin. 
It seems rather to be an insular variant derived, like so many plants of 
the Magdalen Islands and Newfoundland, from the south but by long 
isolation modified into a well pronounced geographic variety. 
Il, THE SABLE ISLAND EPILOBIUM. 
Tue only Epilobium known from Sable Island, 100 miles off the 
coast of Nova Scotia, is a plant collected in 1899 by Professor John 
Macoun and in 1913 secured in quantity by Dr. Harold St. John; 
and from the observations of both these explorers apparently the only 
member of the genus on the island. The plant in habit, outline of 
foliage, and large flowers, as well as in the characters of its calyx and 
seeds, exactly matches the common ŒE. molle Torr. of the mainland, 
while the capsules have the peculiar glandular pubescence which is 
found upon the capsules of E. molle, but in the Sable Island plant much 
more highly developed than is common in mainland specimens. 
The stems and the leaves of the Sable Island plant, however, are 
densely cinereous with appressed and incurved hairs, exactly as in 
E. densum Raf.; E. molle having the stems, leaves, ete., densely cov- 
ered with fine, straight and conspicuously spreading pubescence. 
This Sable Island plant with the technical characters of calyx, 
petals, etc., and the glandular pubescence of the capsule, and the exact 
habit and leaf-outline of E. molle, but with the pubescence of the leaves 
and stems exactly as in E. densum would, if found upon the mainland, 
be promptly called a hybrid between those two species. But neither 
of the species has been detected on Sable Island, a region of sufficiently 
limited area to give assurance that the extended explorations of 
Macoun in 1899, of Giissow in 1911, and of St. John in 1913, when the 
latter explorer spent four weeks in an intensive study of the flora, 
would have brought to light any other existing member of the genus. 
Upon Sable Island, then, this plant, combining the characters of 
two ordinarily distinct species of the mainland, cannot be accepted 
as a hybrid, at least of modern origin. There is, moreover, reason to 
believe that the flora of Sable Island reached that area during the late 
Pleistocene and has been isolated from the mainland flora since that 
time. However long this period may have been, whether estimated 
