s occur in tropical countries. On sandy or
coralline islands in the Malay Archipelago there will often be found a
vegetation consisting almost wholly of cycads, pandani, and palms, while a
few miles off, on moderately elevated land, not a single specimen of either
of these families may be seen, but a dense forest of dicotyledonous trees
covering the whole country. A lowland vegetation, such as that above
described, might be destroyed and its remains preserved by a slight
depression, allowing it to be covered up by the detritus of some adjacent
river, while not only would the subsidence of high land be a less frequent
occurrence, but when it did occur the steep banks would be undermined by
the waves, and the trees falling down would be floated away, and would
either be cast on some distant shore or slowly decay on the surface or in
the depths of the ocean.

From the remarkable series of facts now briefly summarized, we learn, that
whenever plant-remains have been discovered within the Arctic regions,
either in Tertiary or Cretaceous deposits, they show that the climate was
one capable of supporting a rich vegetation of trees, shrubs, and
herbaceous plants, similar in general character to that which prevailed in
the temperate zone at the same periods, but showing the influence of a less
congenial climate. These deposits belong to at least four distinct
geological horizons, and have been found widely scattered within the Arctic
circle, yet nowhere has any proof been obtained of intercalated cold
periods, such as would be indicated by the remains of a stunted vegetation,
or a molluscan fauna similar to that which now prevails there.

_Stratigraphical Evidence of Long-Continued Mild Arctic Conditions._--Let
us now turn to the stratigraphical evidence, which, as we have already
shown, offers a crucial test of the occurrence or non-occurrence of
glaciation during any extensive geological period; and here we have the
testimony of perhaps the greatest living authority on Arctic
geology--Professor Nordenskjoeld. In his lecture on "The Former Climate of
the Polar Regions," he says: "The character of the coasts in the Arctic
regions is especially favourable to geological investigations. While the
valleys are for the {77} most part filled with ice, the sides of the
mountains in summer, even in the 80th degree of latitude, and to a height
of 1,000 or 1,500 feet above the level of the sea, are almost wholly free
from snow. Nor are the