848 
ELEMENTS OF GEOLOGY. 
the Amphitherium might not be an insectivorous placental, 
although it offered some points of approximation in its oste¬ 
ology to the marsupials, especially to the Myrmecohius^ a 
small insectivorous quadruped of Australia, which has nine 
molars on each side of the lower jaw, besides a canine and 
three incisors.* Another species of Amphitherium has been 
found at Stonesfield (Fig. 345), which differs from the former 
(Fig. 344) principally in being larger. 
Fig. 345. Fig. 346. 
Amphitherium Broderipii, 
Owen. Natural size. 
Stonesfield Slate. 
Phascolotherium Bucklandi, Broderip, sp. 
a. Natural size. 5. Molar of same, 
magnified.. 
The second mammiferous genus discovered in the same 
slates was named originally by Mr. Broderip Didelphys 
Bueklandi (see Fig. 346), and has since been called Phasco- 
lotherium by Owen. It manifests a much stronger likeness 
to the marsupials in the general form of the jaw, and in the 
extent and position of its inflected angle, while the agree¬ 
ment with the living genus Didelphys in the number of the 
pre-molar and molar teeth is complete.f 
In 1854 the remains of another mammifer, small in size, but 
larger than any of those previously known, was brought to 
light. The generic name of Stereognathus was given to it, 
and, as is usually the case in these old rocks (see above, p. 
328), it consisted of part of a lower jaw, in which were im¬ 
planted three dbuble-fanged teeth, differing in structure from 
those of all other known recent or extinct mammals. 
Plants of the Oolite. —The Araucarian pines, which are now 
abundant in Australia and its islands, together with marsu¬ 
pial quadrupeds, are found in like manner to have accom¬ 
panied the marsupials in Europe during the Oolitic period 
(see Fig. 348). In the same rock endogens of the most per¬ 
fect structure are met with, as, for example, fruits allied to 
the Pandanus, such as the Kaidacarpum ooliticum of Car- 
ruthers in the Great Oolite, and the JPodoearya of Buckland 
(see Fig. 347) in the Inferior Oolite. 
FulleFs Earth. —Between the Great and Inferior Oolite 
near Bath, an argillaceous deposit, called “ the fuller’s earth,” 
* A figure of this recent Myrmecobius will be found in my Principles of 
Geology, chap. ix. 
t Owen’s British Fossil Mammals, p. 62. 
