Review of Recent Geological Literature. 339 
formations which are met with in the same horizons. The probability of 
the Permian age of these formations has been made far more certain by 
the recent contributions to this subject from the discoveries in the salt 
range which put the question in a new light. 
In the salt range the glacial evidences of the "Olive Group" have long 
been known. Transported glacial boulders of an older Paleozoic age are 
embedded in a formation that underlies the Permian. It has also been 
noticed that no post-Carboniferous remains are found in this glacial for- 
mation which contains nodules with organic remains, nearly half of 
whose species are identical with those of the Australian coal measures. 
While utilizing the data obtained by Oldham and Wynne, Dr . Waagen, 
shows that the glacial indications observed by them at various localities, 
all belong to the same formation instead of different ones, as they sup- 
posed. There can be almost no doubt, then, according to all the rules of 
synchronism, that the glacial formations of the salt range are to be re- 
garded as of the same age as those of Australia, whose fauna are so large- 
ly identical. In Australia we have the lower Carboniferous beneath; in 
the salt range are unquestionable Permian strata above. With regard to 
the change in plant life at the appearance of this glacial epoch, it was 
natural that the older true Paleozoic species such as those Caiamites and 
Lepidodendron should hardly survive so great a change of temperature. 
In the increasing coldness which the glacial advance brought on, the 
older and more delicate types were forced to give way and only the hardier 
forms and such variations as were developed amid, and enabled to survive 
the exigencies of a gradually changing climate, remained to form the 
nucleus of rich IVIesozoic flora which followed. A further conclusion 
which the author derives is that the Mesozoic plant types which originated 
in the Carboniferous epoch on this great southern Africo-Indo- Australian 
continent are autochthonous t here and that the European Mesozoic flora 
which possesses so great a similarity is to be regarded as descending from 
this Paleozoic flora which at the time of the coal-measures gave it origin 
in the southern continent. The great factor is glaciation which the author 
supposes to have extended from about 40° south latitude to 85° north, 
and from 35° east to 170° east from Feno, an area which included 
more than one-fourth of the earth's surface. 
With regard to the claims for a Paleozoic glacial epoch in Europe the 
author gives a comprehensive discussion. Though, contrary to the 
opinions of Geike, he doubts the probability of a glacial origin for the 
conglomerates at the base of tlie Carboniferous in the south of Scotland; 
he regards the indications furnished in the Permian breccias of the British 
Isles, especially the midland counties of England, the conglomerates of 
the Upper Carboniferous in France as well as the more important evidences 
in the Silesian coal-fields, the Alps of the Gail, and various other areas of 
Europe, as demonstrating almost beyond doubt the occurrence of glacia- 
tion in the upper division of the Permian. A fact of the greatest import- 
ance ii the transition from the Paleozoic to the Mesozoic floras accompanied 
by the extinction of the greater part of the Paleozoic types in the middle 
Permian, contemporaneous!}' with the occurrence of the glaciil phenomena. 
