190 DISCUSSIOFS IN CLIMATOLOGY. 



Equally conclusive is the testimony borne by the 

 Mollusca of the tufas. In the tufas and marls of 

 Moret, in the valley of the Seine, 35 species were dis- 

 covered. The majority of these must have lived in 

 damp and shady places, in the recesses of moist woods, 

 and on the leaves of marsh-plants. The shells, M. 

 Tournouer concludes, bespeak a condition of climate 

 more uniform, damp, and equable than now prevails 

 in that region, with a somewhat higher mean annual 

 temperature. In the alluvial deposits of Canstadt, in 

 Wiirtemberg, a class of shells indicating a similar 

 condition of climate has been discovered. 



The evidence furnished by the animals found most 

 abundantly with the mammoth in Europe and Siberia, 

 Mr. Howorth thinks, points to the same conclusion as 

 the testimony of the plants and mollusca associated 

 with that huge mammal. 



The same mild and equable condition which allowed 

 of the mammoth living in Northern Siberia during 

 Pleistocene times thus equally prevailed over the whole 

 of Europe. We have seen that, according to the 

 Physical Theory, this condition of climate was in every 

 respect precisely what it ought to have been on the 

 supposition that it was interglacial. It was a condition 

 mild, equable, uniform, humid, and of a higher mean 

 annual temperature than we have at the present day. 

 There is, however, direct and positive evidence that 

 this condition of climate was interglacial ; for the facts 

 both of geology and of palaeontology show that it was 

 preceded and succeeded by a state of things of a wholly 

 opposite character. 



The Mammoth Glacial as well as Interglacial. — 

 Although the mammoth could have lived in Arctic 

 Siberia only during an interglacial period, it does not 

 follow that it must have perished during the succeeding 



