280 REVIEWS 
where a few species indicating a fauna of Utica age have been collected. 
In general the Trenton beds are followed immediately by strata con- 
taining a Silurian (Upper Silurian) fauna of Niagara or Wenlock age. 
STUART WELLER. 
The Glacial Palagonite-Formation of Iceland. By Hevei Pyjeturs- 
son, Cand. Mag. Copenhagen. The Scottish Geographical 
Magazine, May 1900, Vol. XVI, No. 5. 
This appears to be a very important contribution to the history of 
Pleistocene glaciation. It opens up a new and very promising field, 
whose data are peculiar because of their association with volcanic phe- 
nomena. The author presents in much detail, and with apparent care and 
discrimination, evidence of glacial formations antedating the so-called 
“‘preglacial”’ lava flows, as well as others interstratified with the lava 
flows. After twenty-two pages devoted to description of details, illus- 
trated by figures, the author draws the following important conclu- 
sions : 
I shall not be surprised if this account of the occurrence of glacial depos- 
its and striated rock surfaces in connection with the ‘‘ palagonite-formation”’ 
of Iceland is received with incredulity. For myself, I could hardly believe 
the evidence when | first encountered it, and tried to explain it in every pos- 
sible way other than by glacial action. but the glacial origin of the ‘“brec-_ 
cias’’ could not be gainsaid. Not only did they present a characteristically 
morainic aspect, but they yielded numerous well striated stones, and in places 
were found to be resting upon grooved and striated rock surfaces. If the 
observations I have here recorded be accepted as fairly trustworthy, we can- 
not avoid the conclusion that glacial deposits, hitherto unrecognized as such, 
are largely developed in Iceland, or at all events in that part of the island 
which I have critically examined and referred to in these pages. 
As I have had only a glimpse, as it were, into this very promising field of 
glacial research, I shall not attempt to deal with the glacial succession in Ice- 
land. That must be left for future investigations to determine. Nevertheless 
there are several conclusions which seem to me obvious enough. Of these 
the most important, in my opinion, is that which has reference to successive 
glaciations. The facts advanced show that Iceland has experiencéd more 
than one glaciation before the ejection of the doleritic lavas and their subse- 
quent smoothing and grooving by ice. How many separate glaciations the 
morainic breccias bear witness to is uncertain. But the repeated occurrence 
of four separate sheets or beds of morainic breccia seems to render it not 
improbable that there have been just as many separate glaciations during the 
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