On the British Species of Fossil Mastodon and Elephant. 73 
and Loxodon ; others, in which the number of the ridges progressively 
increases, are “‘anisomerous,” and form a third natural group, namely 
the Euelephas or Elephas proper. ‘The Stegodon has four species, 
fossil in India; and approaches the Mastodon in the form of the 
molars. The Lovodon includes the existing African Elephant and 
three fossil species, and is characterized by its distinct rhomboidal 
discs of wear on the grinders. Huelephas has thin-plated molars ; 
but in some species there are intermediate stages, as regards the 
angular mesial expansion of the plates, between it and Lowodon. 
Dr. Falconer next proceeded to review some well-ascertained 
mammalian faunz localized in certain parts of Europe, where the 
conditions of deposit are most simple, and to apply the results to the 
more complex instances, where the remains of more than one di- 
stinct fauna are intermingled, or so closely deposited as to be too 
readily confused by collectors. With this view, the author in- 
stanced the Subapennine or pliocene deposits of the Astesan, and 
elsewhere in Piedmont and Lombardy, where T'rilophodon Borsoni, 
Tetralophodon arvernensis, Loxodon meridionalis, Lox. priscus, and 
Euelephas antiquus, with Rhinoceros leptorhinus, Hippopotamus major, 
&c., are found associated together. In the Subapennine beds of the 
Val d’Arno, in Tuscany, Tetralophodon arvernensis and Loxodon 
meridionalis occur with the same Hippopotamus and Rhinoceros. 
Near Chartres, in France, Loxodon meridionalis accompanies H. 
major and Rhinoceros leptorhinus. The above-mentioned are neces- 
sarily the leading mammalian forms of the older Pliocene period. 
North of the Alps pliocene deposits similar to those of Italy occur in 
some parts of Switzerland, but they are soon overlaid towards the 
north by a distinct mass of erratic drift of a different age and with 
different mammalian remains. In the fluviatile “Loess” or ‘“‘ Lehm”’ 
of the valley of the Rhine, and in the Glacial Drift of the plains of 
Northern Germany, these post-pliocene deposits contain remains 
of the true Mammoth, with the tichorhine Rhinoceros, the Musk- 
buffalo, &c., which thus constitute the leading types of the post- 
pliocene mammalian fauna. 
On the eastern coast of England, the Crag-deposits (the Red and 
Norwich Crags) yield the pliocene Tetralophodon arvernensis, Low- 
odon meridionalis, and Euelephas antiquus ; and the so-called Elephant- 
beds at Cromer, Mundesley, and Hasborough furnish Low. meri- 
dionalis and Euel. antiquus, with Rhin. leptorhinus and Hip. major. 
These characteristically pliocene fossils, however, are occasionally 
intermingled with the remains of the post-pliocene Huelephas primi- 
genius, the latter fossils having been derived from the overlying and 
later drift-beds, which have thus proved a fertile source of the 
confusion and ambiguity already referred to. To some extent, 
similar conditions exist at Bracklesham Bay and Pagham Harbour, 
where molars of EH. primigenius are found in the upper gravels, 
whilst remains of #. antiquus abound in the older mud-deposit, 
lately described in the Society’s Journal by Mr. Godwin-Austen. 
Dr. Falconer then considered the fluviatile deposits of the Valley 
of the Thames, in relation to their Elephantine remains ; especially 
