172 Louis Figuier. [April. 



says, " These were formerly considered so closely allied to tropical 

 genera, and so ranch, greater in size than the corresponding tribes 

 now inhabiting equatorial latitudes, that they were thought to imply 

 an extremely hot as well as hnmid and equable climate. But 

 recent discoTeries respecting the structure and relations of these 

 fossil plants have shown that they deviated so widely from all 

 existing types in t-: vegetable world, that we have more reason to 

 infer, from this evidence, a widely different climate in the Car- 

 boniferous era as compared to that now prevailing, than a tem- 

 perature extremely elevated." 



With regard to the physical formation of the beds of coal, 

 If. Figuier embraces the theory generally accepted, that the plants 

 grew and decayed in the places in which we now find the coal, 

 and were not drifted from a distance. 



He concludes his account of the primary rocks with a description 

 of the Permian strata, and of the life of the Permian period. An 

 awkward tact for the consideration of those who defend the theory 

 of a high temperature in the crust of the earth itself at this epoch 

 is thus noticed :* — u Although the Permian flora indicates a climate 

 similar to that which prevailed during the Carboniferous period, if 

 has been pointed out by Professor Ramsay as long ago as 1855, that 

 the Permian breccia of Shropshire, Worcestershire, &c, affords strong 

 proofs of being the result of direct glacial action, and of the conse- 

 quent existence at this period of glaciers and icebergs. That such a 

 state of things is not inconsistent with the prevalence of a moist, 

 equable, and temperate climate, necessary for the preservation of a 

 luxuriant flora, like that of the period in question, is shown in New 

 Zealand, where, with a climate and vegetation approximating to 

 those of the Carboniferous period, there are also glaciers at the 



ait day, in the southern island." 



We can see no analoi" - :~ een the climate of New Zealand 

 and the state of things descril A by 31. Figuier as existing during 

 the Carboniferous age, although there can be little doubt that the 

 actual climatal condition of the greater part of the earth during 

 C :._": miferona and Permian times was something similar to that 

 prevailing in New Zealand at the present day. That glaciers could 

 not exist upon a surface having an elevated temperature, due to the 

 conduction of heat from beneath, is self-evident. 



The close of the Primary epoch was, he supposes, marked by 

 local convulsions and disturbances of the globe; but we need not 

 i : ;ur to any general cataclysm to explain the passages from one 

 epoch to another, for we have seen, almost in our own day 

 species of animals die out and disappear gradually. 



The life of the globe during the Palaeozoic ages was charac- 

 terized by very peculiar forms, both in the animal and vegetable 

 kingdoms. The Graptolites and Cystidea of the Silurian rocks, 



* P. 153. 



