Prof. K. A. von Zittel—On the Mammaha. 513 
the same orders in the three continents have had sufficient time to 
become specialized in an altogether peculiar manner. How at the 
close of the Tertiary period the Southern and the Northern half of 
America grew together, and how the faunas of both divisions were 
mutually pushed over and through each other, has already (pp. 504- 
505) been sufficiently described. 
Il]. The third and largest zoo-geographical kingdom, the 
Arctogzan, includes not only Europe, Asia, and Africa, but also 
North America. Although all Paleontological traditions respecting 
the older Tertiary period in Asia and Africa are up to now still 
wanting, nevertheless, neither the prolific Mio-Pliocene mammalian 
fauna of Asia, nor the scanty remains from the younger Tertiary 
formations of Africa, nor the composition of the still existing fauna 
of South Asia and Africa, can give rise to even a suspicion that along 
with the known Mammalian races in the older Tertiary of Kurope 
and North America, there could have originated yet another hetero- 
genous fauna in any part whatever of Eurasia. The Tertiary forms 
of Europe and North America, known up to the present, completely 
suffice to show that the Mammals of Europe, Asia, Africa, and 
North America are derived from them (with the exception of some 
forms conjectured to have wandered from Australia and South 
America). The Palearctic, Nearctic, Ethiopic and Indian kingdoms 
of Sclater and A. R. Wallace form for the Mammals (as Huxley has 
already pointed out) a single distribution region, which indeed, 
during the Tertiary and Diluvial periods became already split up 
into several provinces. The connection with North America was 
the earliest to be loosened, and already in the Miocene and Pliocene, 
the New World stood, as against the Old, as an independent zoo- 
geographical province; which, indeed, after the Ice-age, again 
received some northern guests, probably from Hastern Asia. To 
Southern Asia and Africa a portion of the heat-loving animals, 
especialy Ungulates, Carnivora and Apes, withdrew themselves at 
the close of the Tertiary period and peopled a province which 
reached from the West Coast of Africa as far as the Chinese Sea, 
and may still further have embraced the coast districts of the 
Mediterranean Sea. In the newer Tertiary period, Ceylon, the 
Sunda Islands, the Philippines, and Madagascar certainly stood in 
connection with the neighbouring continents, and received from 
these their supply of land Mammals. Africaand South Asia even now 
possess a number of genera in common, and they contain, strictly 
taken, a single mammalian fauna which probably as late as the 
Diluvial period became so far differentiated that it can to-day be divided 
into two independent provinces. Madagascar, with the Mascarene 
Islands, maintains the same rank as the Indian and Hthiopian 
provinces. The land Mammals of this small region display unmis- 
takable features of a great isolation at an early period. Excepting 
the Swine, and some small, as a rule, passively wandering Rodents, 
most of the Mammals belong to peculiar, specifically Madagascar 
genera. The numerous Lemurs call to mind their Upper Hocene 
forerunners in Hurope, and even the Carnivora (Cryptoproctide) 
DECADE III.—VOL. X.—NO. XI. 33 
