OF MAMMALIA. 601 
the realm, whilst all the other families are present. Of 
Ungulata all the families of Perissodactyla and Artiodactyla 
are found, and all are confined to the realm except the pigs, 
tapirs, camels and deer. In addition, the two sub-orders of 
the elephants and hyraces are only found here. Of Jnsecti- 
vora, the realm has almost a monopoly, one family alone 
(the Solenodontide of West Indies) being found outside its 
borders. The lemurs are also confined to the realm, as 
are three of the anthropoid families. 
Thus the realm has a practical monopoly of the order 
Lnsectivora and of the large order Ungulata (except four 
families), including the whole of the two sub-orders Pro- 
boscidea and Ayracoidea, of the sub-orders Momarthra and 
Lemuroidea, three families of the cosmopolitan Carnivora 
and three (of five) of the Anthropoidea, besides a great 
number of rodent families. On the other hand, the 
absence of Prototheria, and all the families of AMetalheria 
but one, is equally diagnostic. 
The past history of Arctogcea shows that in the secondary epoch its 
fauna was remarkably uniform, not only as regards reptiles but in 
mammals. Of these the Prototheria were represented by the Al/otheria 
occurring in Europe, North-America and Africa, and the Aetatheria 
by numerous small Polyprotodontia from North America and Europe. 
No evidence of Zutherza in this realm (or indeed anywhere else) has yet 
been forthcoming from secondary strata, and we have already seen that 
at this period (Jurassic and Cretaceous) Notogcea was in direct con- 
nection with this realm, as probably was Neogcea as well. Thus all the 
realms probably had much the same reptilian and early mammalian 
fauna. At the base of the Eocene, there appear early Lemuroidea and 
very primitive Carnivora (Creodonta) and Ungulata (Condylartha) ; 
all were very generalised with simple tritubercular teeth and penta- 
dactyle limbs. During the Eocene the greater number of the orders 
make their first appearance, together with numerous types now extinct, 
and at the commencement of this period, the Metatherian types dis- 
appear, with the exception of the opossums. Hence the Arctogeean ~ 
realm assumed its general diagnostic characters in early Tertiary times 
and has continued onwards to differentiate into several important regions. 
Apparently it has by later communication given ofits types considerably 
to Neogcea and to some extent (incidentally) to Notogcea, but has received 
from them very little except perhaps a few Zdentata from the former. 
Arctogcea can be divided into five regions, as follows :— 
(1) Madagascar and adjacent islands; (2) Ethiopian, or 
Africa south of the Sahara; (3) Oriental—India, southern 
India and Malay; (4) Holarctic—the rest of Asia, Europe 
