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LEMURS. 
Extinct Lemurs. 
We have already incidentally referred to the occurrence of several fossil 
lemurs in the lower Tertiary strata of Europe; but it remains to he mentioned that 
other species have been found in the corresponding rocks of North America. This 
is a very curious and highly important circumstance, since it suggests that while the 
New World monkeys and marmosets, which have very lemur-like molar teeth, may 
have taken their origin directly from the extinct lemurs of that hemisphere, the Old 
World monkeys may have had an independent origin from the ancient lemurs of 
Europe. 
Curiously enough, although the remains of lemurs have been known for very 
many years from the lower Tertiary rocks, both of Hampshire and France, it is 
only quite recently that they have been recognised as such, having been long 
regarded as belonging to small hoofed mammals. One of these groups of lemurs, 
represented by several species of different, though relatively small, dimensions, 
occurring both in England and France, has been described under the name of 
Microchoerus; the term meaning “ small pig,” and having been applied from the 
supposed affinity of the creature to the hoofed mammals. These animals were 
undoubtedly lemurs nearly allied to living forms, their skulls being very like those 
of the galagos, although their upper premolar teeth more nearly resembled those 
of the mouse-lemurs. Like all other fossil lemurs, they are, however, distinguished 
from living forms by the circumstance that the place and form of the lower tusk 
is not taken by the first of the lower premolar teeth (see p. 203). This is a very 
important circumstance, since it shows that these ancient lemurs were what zoologists 
call less specialised than their living relations, and also removes any difficulty as 
to the descent of monkeys (in which the lower tusk always remains) from lemurs. 
Another and larger European Tertiary lemur, known as the Adapis, carries 
the series one step still further back, since it has four premolar teeth on either side 
of each jaw; whereas, as we have seen, no living lemur has more than three of 
these teeth. Here, then, so far as it goes, we have decisive evidence of the 
approximation of the extinct lemurs to the inferior 
orders of Mammals, among which four premolar teeth 
are frequently present; and we may thus hope in time 
to discover further evidence of intermediate forms. 
Some of the extinct North American lemurs, 
with four premolars, do indeed exhibit certain tran¬ 
sitional characters; but it would be beyond the 
province of the present work to enter upon their 
discussion. 
There have recently been discovered in the superficial deposits of Madagascar 
the remains of a gigantic extinct lemur, described under the name of Megaladapis. 
The skull presents some resemblance to that of Adapis ; but the upper molar teeth 
are triangular. Like many of the foregoing this lemur indicates a family by itself. 
Not improbably it was living about two centuries ago. 
THE LEFT UPPER CHEEK-TEETH OF AN 
EXTINCT EUROPEAN LEMUROID 
(Adapis). 
