ON BRITISH FOSSIL MAMMALIA. 209 
Observation, which ought to precede all hypothesis, as it alone can form 
the basis of any sound one, has shown in the first place that the remains of 
the Elephants which are scattered over Europe in the unstratified superficial 
deposits called ‘ Diluvium,’ ‘ Drift,’ ‘ Till,’ ‘ Glacio-diluvium,’ as well as those 
from the upper tertiary strata, are specifically different from the teeth and 
bones of the two known existing Elephants, the Hlephas Indicus and El. 
Africanus. This fundamental fact, when first appreciated by Cuvier, who 
announced it in 1796, opened to him, he says, entirely new views of the 
theory of the earth, and a rapid glance, guided by the new and pregnant 
idea, over other fossil bones, made him anticipate all that he afterwards 
proved, and determined him to consecrate to this great work the future years 
of his life. 
The differences which the skull of the fossil Elephant presents as compared 
with the recent species are, the more angular form and relative shortness of 
the zygomatic processes; the longer, more pointed and more curved form 
of the postorbital process ; the larger and more prominent tubercle of the la- 
chrymal bone ; the greater length of the sockets of the tusks ; the more parallel 
position of the right and left sockets of the grinders, making the anterior in- 
terspace and channel at the junction of the rami of the lower jaw proportion- 
ably wider than in the existing Elephants. Of the differences in the confor- 
mation of the skull above enumerated, I have verified the last-mentioned 
instance, taken from the lower jaw, by observation of English specimens ; 
they are well displayed in the lower jaw of a young Mammoth disinterred 
from a Pleistocene bed near Yarmouth in the county of Norfolk, and now in 
the possession of Mr. E. Stone, of Garlick Hill, London. 
This lower jaw shows also that the outer contour of one ramus meets that 
of the other at a more open angle than in the African or Asiatic Elephant, 
and that the symphysis itself, though acute at this period of life, is less pro- 
longed. In the older Mammoths the symphysis becomes obtuse; were it 
otherwise, the prolonged alveoli of the fully-developed tusks would have in- 
terfered with the motion of the lower jaw. 
The difference between the extinct and existing species of Elephant in re- 
gard to the structure of the teeth, has been more or less manifested by every 
specimen of fossil elephant’s tooth that I have hitherto seen from British 
strata, and those now amount to upwards of three thousand. Very few of 
them could be mistaken by a comparative anatomist for the tooth of an 
Asiatic Elephant, and they are all obviously distinct from the peculiar molars 
of the African Elephant. 
_ Cuvier, who had recognized a certain range of variety in the structure of 
the numerous teeth of the Mammoth from continental localities, found never- 
theless that the molars of the fossil Elephant were broader in proportion to 
their length or antero-posterior diameter than in the existing species; that 
the transverse plates were thinner and more numerous in the fossil molars 
than in those of the Indian Elephant; that a greater number of plates entered 
into the formation of the grinding surface of the tooth, and that the lines of 
enamel were less festooned ; but to this character there are exceptions, espe- 
cially in the large molars of aged individuals. 
Varieties.— Question of Species. 
The varieties to which the grinders of the different species of Elephants 
are subject in regard to the thickness and number of their plates, increase in 
the ratio of the average number of the plates which characterizes the molar 
teeth of the different species. Thus in the African Elephant, in which the 
lozenge-shaped plates are always much fewer and thicker than the flattened 
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