256 The Creodonta, (March, 
while the smaller forms, representing in function the civets and 
weasels of to-day, were especially numerous. 
The systematic position of these animals has been difficult to 
determine with satisfactory precision, owing to the impertet 
= knowledge which we possess of their structure. Besides lack of 
scapholunar bone, they nearly all differ from the Carnivora in ther 
ungrooved astragalus, and their greatly reduced and smooth 
cerebral hemispheres. Their position then can only be with the 
Marsupialia or the Insectivora. The superficial resemblances art 
often to the former order, where the carnivorous types Thylacinus, 
Sarcophilus, Dasyurus and the opossums, seem to present neat 
affinities, if the structure of the teeth only is to be considered. 
Laurillard, DeBlainville and Gaudry have, at different times, 3 
signed to them this position. It is true, however, that no om 
osseous character, except the possession of marsupial bones, hs 
yet been discovered which characterizes the order Marsupialia. | 
It rests chiefly on the characters of its soft parts, especially 0 
the brain and reproductive system. Most marsupials have th l 
angle of the lower jaw inflected ; the Eocene flesh-eaters do nt 
The carnivorous marsupials generally have more than ix” | 
teeth ; the Eocene flesh-eaters have six or less. The m fa i 
generally have perforated palates; the Eocene forms e 
play the character. No marsupial bones have yet been ef m 
the Eocene forms (with the possible exception of Mioclænus) A 
that we cannot yet find the necessary reasons for placing ee 7 
tinct forms with the order which possesses them. On : 
hand the brain was probably marsupial in its internal sap 
as it certainly was in its external character. Finally s a 
covery of the character of the temporary dentition 1m the oe 
flesh-eaters has added force to the view that they cannot we 
supiils. M. Filhol has shown that in Hyanodon ae 
three temporary molars, and I have proven that there but 0% 
least two in Triisodon. There is, according to Flow’ n trot 
in the Marsupialia. It is, however, to be remembered th a 
marsupials, opossums, occur in the Oligocene In that thf 
America and Europe (genus Peratherium Aym.), ania in Be 
resemble their Eocene predecessors very much, especial a 
constitution and form of the molar teeth. ch fundë 
The comparison with the Insectivora betrays 9° ife” 
mental diversities as that with the Marsupialia. The w 
