148 Scientific Intelligence. 
the vegetation, say of the 35th parallel in the Atlantic United 
States, has once b s far north as the 60th parallel; and the 
intertropical flora had advanced to London at the commencement 
of the Tertiary period. In another connection he remarks that, 
“i] est 4 peu prés démontré que les flores actuelles des Etats- 
Unis méridionaux et d on se sO rochées un fois dans le 
nord, sous Pempire de climats tempérés, selon ’hypothése émise, 
en 1859, par Ww endeavors to trac 
: unas are very 
similar, but in widely separated latitudes (say Spitzbergen and 
middle Europe for a marked instance), they cannot possibly have 
eous. For diff 
since the temperature has on the whole diminished in the course 
of ages, and especially during the Tertiary epochs, And not only 
very different fossil Tertiary floras must have been contempora- 
neous in different latitudes, but probably under the same parallels 
