■Wll 
INT1{()DIJCT1()X. 
iiiiiTierically, but increase greatly in size and number ef transverse ridges. Di’. Clialmers 
INIitcliell lias lately shown ('IVans. Zool. Soc. vol. xvii. 1905, ])[). 464-7) that tlieSirenia 
and Troboscidea resrunble one another in the arrangement of the intestinal tract and 
that in neither groiqi is there any trace of the Ungulate specialisation : it is also 
signiheant that he* states that Ihjrax likewise approaches the Sirenia in this respect. 
In a former paper (Phil. Trans, vol. 196 b(1903) p. 116) it was stated that the possession 
of a non-deciduate zonary placenta was common to the two groups in question, but it 
has been pointed out by Messrs. Assheton and Stevens (Quart. Journ. Micr. Sci. vol. xlix. 
1905, p. 1) that this is an error, and that, as a matter of fact, in the Proboscidea the 
placenta is deciduate. At the same time, these writers show that in both groups 
the placenta, in addition to the short villi, also possesses a number of larger and longer 
\ illi, which deeply penetrate the maternal tissue and seem to be torn off at parturition. 
Although these ]ioints of similarity, taken separately, may be of no great value, 
together they supply a very strong argument in fiivour of the close relationship of the 
two orders. 
All the Carnivora at present known from the Upper Eocene of the Fayum belong 
to one family, the llycenodontida?, of the primitive group, the Creodonta. They are 
remarkable from the fact that in the four genera represented, 's iz. Sinopa, Aptcrodon, 
Fterodon, and Ihjoenodon, the molar teeth show four stages in the development of the 
cutting-blade and in the reduction of the talon and the postero-internal cusp. It 
seems highly probable that these animals entered Africa from the north, where 
Creodonts are found in the earlier Eocene deposits ; but at the same time the fact that 
the Zeuglodont Protocetus from near the bottom of the Lower Mokattam beds, has a 
dentition which is practically that of a Creodont, clearly indicates its origin from 
members of that group, which may therefore have inhabited this region at a still 
earlier period. Since, liowever, Protocetus is already fully adaj)ted for marine life, 
this is by no means certain, for it may have crossed from the northern side of the 
Nummulitic sea. Another argument for the existence of earlier Creodonts in 
the Egyptian region is that, since there is considerable probability that Africa was 
connected by a land-bridge with South America in late Cretaceous and jmssibly even 
at the beginning of the Tertiary period, their presence in Africa would account for 
the existence of the Sparassodonta in the Tertiaries of Patagonia. 
'Ilie Zeuglodonts of the Fayum, taken together with a species, Protocetus atavus, 
recently described by Prof. E. Fraas (29) from the limestones of the Mokattam Hills, 
form a series showing a complete transition, so far at least as the dentition is concerned, 
