436 Scientific Intelligence. 
An obvious result of such partial extinction is clearly enough brought 
to view. The European Oaks (like the American species) greatly tend 
to vary,—that is, they manifest an active disposition to produce new 
forms. Every form tends to become hereditary, and so to pass from the 
o Linneus this Common Oak of Europe was all of one species, 
But of late years the greater number of European botanists have re- 
garded it as including three species, Q. pedunculata, Q. sessiliflora, and 
Q. pubescens. DeCandalle looks with satisfaction to the independent 
conclusion which he reached from along and patient study of the forms 
(and which pia Gay, Bentham and others had ia reached), that 
the view of Linnzus was correct, inasmuch as it goes to show that 
idea and the ponciital application of the term spenee gece remained un- 
changed during the century which has elapsed since the pabliasigns 
the Species Plantarum. _ But the idea remaining unchanged, the facts 
under a slight and very supposable change of circumstances, 
= —— varicties of Q. Robur, which Decadal Te 
no means the most common. Were these to die out, it is clear that t 
three forms which have already baie so frequently taken for species, wot 
be what the group of four or _— nes admitted species Wh : 
closely surround Q. Robur (see p. 435) now are. The best ee 
such a case, as having in all probability occurred, through geogr or 
segregation and partial extinction, is that of the Cedar, thus opal 
-into the Deodar, the Lebanon, and the Atlantic st Ro case admirably 
worked out by Dr, aslags two or three years ‘chet 
A special advantage of the Cupulifere for determining the 
antiquity of existing species in Europe, DeCandolle finds in th 
character of their fruits. However it may be with other plants We 
e size and 
natural causes across an sete of the sea ina adie to seri os bore oe 
much more the spontaneous establishment of a forest of or ©. 
nuts in this way, DeCandolle conceives to be fairly im mpousible in i 
~ contrary to * experience. From such considerations, i, Gr from 
dispersion of the existing species, with occasi | 
aie deposit - - thought to be shown that the principal C 
of the Old W. ained their actual extension before the 
— of Bic ily, Sardinia and Corsica, or of Britain, from the 
_ This view once ma and this course once entered upon, an 
ursned farther. Quercus Robur of Europe with its bevy of admis 
jew, Jan., 1862. See this Journal, [2], xxxiv, 148. 
