Dr. J. Croll on Arctic Interglacial Periods. dl 
organic remains belonging to a mild interglacial period 
cannot therefore be adduced as evidence against the probable 
existence of such a period. Who would expect to find such 
remains in ice-covered regions like Greenland and Spitzber- 
gen? Although not a trace is now to be found, it is never- 
theless quite possible that during interglacial periods those 
regions may have enjoyed a comparatively mild and equable 
climate. 
Evidence from the Mammoth in Siberia.—This comparative 
absence of the remains of a warmer condition of climate in 
Arctic regions during Pleistocene times holds true, however, 
only in regard to those parts, like Greenland, which have 
undergone severe glaciation. When we examine Siberia 
and other places which appear to have escaped the destructive 
power of the ice, we find, from a class of facts the physical 
importance of which appears to have been greatly overlooked, 
abundant proofs of a mild and equable condition of climate. 
I refer to facts connected with the climatic condition under 
which the Siberian Mammoth and his congeners lived. The 
simple fact that the Mammoth lived in Northern Siberia 
proves that at the time the climate of that region must have 
been far different from what it is at the present day. 
The opinion was long held, and is still held by some, that 
the Mammoth did not live in Northern Siberia, where his 
remains are found, but in more southern latitudes, and that 
these remains were carried down byrivers. It was considered 
incredible that an animal allied to the Elephant, which 
now lives only in tropical regions, should have existed under 
a climate so rigorous as that of Siberia. The opinion that 
the remains were floated down the Siberian rivers is now, 
however, abandoned by Russian naturalists and other observers 
who have carefully examined the country. 
I shall here give a brief statement of the facts and argu- 
ments which have been adduced in support of the theory that 
the Mammoth lived and died where its remains were found. 
For these facts Iam mainly indebted to the admirable papers 
by Mr. Howorth on the “ Mammoth in Siberia,” which 
appeared in the ‘ Geological Magazine’ for 1880. 
Had the remains of the Mammoth been carried down from 
the far south by the Siberian rivers, they would have been 
found mainly, if not exclusively, on the banks of the long 
rivers, such as the Obi, Yenissei, and the Lena, and in the 
deltas formed at their mouths. But such is not the case, 
‘‘hese are,” says Mr. Howorth, “found even more abun- 
dantly on the banks of the very short rivers east of the Lena, 
They are found not only on the deltas of these rivers, but far 
