468 Transactions.— Geology. 
to obtain, the peculiar reptilian fauna which characterizes this period indi- 
cating unmistakably the existence of a warm temperature in the seas, 
lakes, and rivers, whilst the flora supports the hypotheses of Heer, 
Adolphe Brogniart, and others, that the climate of Europe, even within 
123° at the Pole, must have resembled that of the West Indies at the 
present day. 
I might repeat the same language with regard to the Triassie, Jurassie, 
Carboniferous, Devonian and Silurian periods, all of which afford similar 
evidence, but I prefer quoting the following general remarks on the subject, 
with which Sir Charles Lyell concludes the eleventh chapter of his work :— 
** The result, then, of our examination in this and the preceding chapter, of 
the organic and inorganic evidence relating to the climate of successive 
geological periods, is in favour of the opinion that a warmer temperature 
generally prevailed in the northern hemisphere from the 30th parallel of 
latitude to the pole than that now experienced. In the Pliocene era the 
fauna and flora of Central Europe were sub-tropical, and a vegetation 
resembling that now found in Northern Europe extended into the arctic 
regions as far as they have been yet explored, and probably reached the 
pole itself. In the secondary or Mesozoic ages, the predominance of reptile 
life, and the general character of the fossil types of the great class of 
vertebrata, indicate a warm climate and an absence of frost between the . 
40th parallel of latitude and the pole, a large Ichthyosaurus having been 
found in latitude 17° 16’, and the general character of the Mollusca and 
corals, as well as of the plants, being in perfect accordance with the 
inferences deduced from the fossil reptiles. If we carry back our retrospect 
to the primary, or Paleozoic ages, we find an assemblage of plants that 
imply that a warm, humid, and equable climate extended in the Carboni- 
ferous period uninterruptedly from the 30th parallel of latitude to within a 
few degrees of the pole, or to northern regions where at present the severe 
winter’s frost and the akmost universal covering of snow, lasting for many 
months, preclude the existence of a luxuriant vegetation. In rocks older 
than the Carboniferous the evidence of plants, insects, and fish fails us; but 
the invertebrate fauna has such a resemblance to that of the latter primary 
and the older secondary periods as to force us to believe that the climate of 
the temperate and arctic regions was very analogous to that which generally 
prevailed in these subsequent epochs.” 
As before observed, however, Sir Charles, and those who follow him, 
decline to admit that heat radiated from the surface of our globe during its 
seeular cooling from an original heated condition, had any influence in 
producing these observed differences in elimate in the northern regions, 
and attribute them entirely to successive changes in the distribution of land 
