CHAP. IX.] 
MILD ARCTIC CLIMATES. 
179 
Straits of Magellan to Valparaiso — places differing as much in 
latitude as Switzerland and West Greenland ; and the same may- 
be said of North Australia and Tasmania, where, at a greater 
latitudinal distance apart, closely allied forms of Eucalyptus, 
Acacia, Casuarina, Stylidium, Goodenia, and many other genera 
would certainly form a prominent feature in any fossil flora now 
being preserved. 
Mild Arctic Climates of the Cretaceous Period . — In the Upper 
Cretaceous deposits of Greenland (in a locality not far from 
those of the Miocene age last described) another remarkable flora 
has been discovered, agreeing generally with that of Europe and 
North America of the same geological age. Sixty-five species 
of plants have been identified, of which there are fifteen ferns, 
two cycads, eleven coniferse, three monocotyledons, and thirty- 
four dicotyledons. One of the ferns is a tree-fern with thick 
stems, which has also been found in the Upper Greensand of 
England. Among the conifers the giant sequoias are found, 
and among the dicotyledons the genera Populus, Myrica, Ficus, 
Sassafras, Andromeda Diospyros, Myrsine, Panax, as well as 
magnolias, myrtles, and leguminosse. Several of these groups 
occur also in the much richer deposits of the same age in North 
America and Central Europe ; but all of them evidently afford 
Such fragmentary records of the actual flora of the period, that 
it is impossible to say that any genus found in one locality was 
absent from the other merely because it has not yet been found 
there. On the whole, there seems to be less difference between 
the floras of Arctic and temperate latitudes in Upper Cretaceous 
than in Miocene times. 
In the same locality in Greenland (70° 33' N. Lat. and 52° 
W. Long.), and also in Spitzbergen, a more ancient flora, of Lower 
Cretaceous age, has been found ; but it differs widely from the 
other in the great abundance of cycads and conifers and the 
scarcity of exogens, which latter are represented by a single 
poplar. Of the thirty-eight ferns, fifteen belong to the genus 
Gleichenia now almost entirely tropical. There are four genera 
of cycads, and three extinct genera of conifers, besides Glyptos- 
trobus and Torreya now found only in China and California, six 
species of true pines, and five of the genus Sequoia one of which 
