72 SECONDARY SERIES. 
abundant of the saline compounds formed by 
sublimation in the craters of volcanoes. 
With respect to the state of animal life, dur- 
ing the deposition of the Secondary strata, 
although the petrified remains of Zoophytes, 
Crustacea, Testacea, and Fishes, show that the 
seas in which these strata were formed, like 
those which gave birth to the Transition series, 
abounded with creatures referrible to the four 
existing divisions of the animal kingdom, still 
the condition of the globe seems not yet to have 
been sufficiently advanced in tranquillity, to 
admit of general occupation by warm-blooded 
terrestrial Mammalia. 
The only terrestrial Mammalia yet discovered 
in any secondary stratum, are the small marsu- 
pial quadrupeds allied to the Opossum, which 
occur in the oolite formation, at Stonesfield, near 
Oxford. The jaws of two species of this genus 
are represented in Plate 2. a. b ; the double roots 
of the molar teeth at once refer these jaws to 
the class of Mammalia, and the form of their 
crowns places them in the order of Marsupial 
animals. Two other small species have been 
discovered by Cuvier, in the tertiary formations 
of the basin of Paris, in the gypsum of Mont 
Martre. 
salt mines of Wieliezka and Sicily are in tertiary formations; 
those of Cardona in cretaceous ; some of those in the Tyrol in 
the oolites ; and near Durham there are salt springs in the coal 
formation. 
