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1891.] A Sketch of the Geology of South America, 859 
I cannot conclude my remarks upon the Mesozoic formations 
of South America without mentioning the two following pecu- 
liarities. The first is the fact that, wholly independent of the 
marine Cretaceous deposits of the Cordillera on the Pacific coast 
of South Chili, glauconitic sandstones are found which contain 
a rich fauna of the uppermost Cretaceous, especially on the Island 
of Ouiriquina. Besides many Ammonites and Baculites, partly 
identical with those from South India, this fauna is characterized 
by the abundance of Gastropods ofa Tertiary type. The Cre- 
taceous beds are covered conformably by a lignitic formation, 
whose fauna does not contain the Cretaceous fossils; but strati- 
graphically both formations are intimately united. So acurious 
parallelism seems to exist in these deposits of South Chili, 
with the Chico-Tejon group of North California. 
The second point to be pointed out is the abundance of eruptive 
rocks within the Triassic, Jurassic, and Cretaceous formations of the 
Cordillera. On the western side of the border of Chili and Peru, 
where the marine deposits of these formations predominate, only a 
very small part of the rocks are formed by Misaone, clay slates, 
or sandstones. These appear , however, tob id between strati- 
fied masses of Dropiyriic, melápliyric; and andesitic material, the 
entire thickness of which strata reaches several 1000 meters. So far 
as we know, this is the largest area of eruptive formation of 
Mesozoic time. The Cordillera of South America is famous for 
its eruptive formations of the latest time, but it merits no smaller 
attention for its submarine eruptions during the Mesozoic time, 
and for the injection of the Mesozoic strata by truly granitic 
and dioritic rocks. 
The Tertiary formations, well developed in the erent 
Republic, have been subdivided into a number of groups by Doring. 

-According to the researches of Ameghino, the younger Tertiary 
deposits of South America show a remarkable peculiarity. This 
paleontologist discovered the remains of human beings not only 
in the Pliocene, but also in the Miocene, deposits. I must confess 
that, comparing the European Mesozoic strata with those of South 
America, quite another classification of the latter seems to be indi- 
cated. What has been called the Pampean formation in the Argen- 


