If we then examine the Miocene
formations of the same country, exotic forms become more abundant, especially
the palms, whether they belong to the European or American fan-palms, Chamaerops
and Sabal, or to the more tropical family of the date-palms or Phoenicites,
which last are conspicuous in the Lower Miocene beds of Central Europe. Although
we have not found the fruit or flower of these palms in a fossil state, the
leaves are so characteristic that no one doubts the family to which they belong,
or hesitates to accept them as indications of a warm and sub-tropical climate.
When the Miocene formations are traced to the northward of the 50th degree of
latitude, the fossil palms fail us, but the greater proportion of the leaves,
whether identical with those of existing European trees or of forms now unknown
in Europe, which had accompanied the Miocene palms, still continue to
characterise rocks of the same age, until we meet with them not only in Iceland,
but in Greenland, in latitude 70 degrees N., and in Spitzbergen, latitude 78
degrees 56', or within about 11 degrees of the pole, and under circumstances
which clearly show them to have been indigenous in those regions, and not to
have been drifted from the south (see Chapter 15).
Pages:
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416