862 



SCIENCE. 



[N. S. Vol. XII. No. 310. 



until our time, and thus we find existing on 

 the Central American and Brazilian coasts 

 the same species of mangrove plants, and 

 with them numerous identical forms of 

 Crustacea, Mollusca, etc.; the distribution 

 of Manatus must also be cited here. 



"We now turn to the relations of South 

 America with Australia and New Zealand. 

 As the views put forth on this point by 

 Hutton and the writer seem to be now gen- 

 erally accepted, there is no reason for dis- 

 cussing the question here. It may be ob- 

 served, however, that not only does the 

 fresh- water fauna give evidence of an ant- 

 arctic land bridge between Australia, New 

 Zealand and Patagonia, but also numerous 

 other zoological as well as botanical and 

 paleontological facts. Osborn says only 

 that this migration established the links 

 with Australia, ' bringing in Marsupials, 

 both polyprotodont and diprotodont. ' 

 Ameghino (Censo, p. 250) says that on 

 this vast antarctic land was distributed the 

 cretaceous mammalian fauna which he has 

 described. No other conclusion is logically 

 possible, and we cannot doubt that the 

 Eocene fauna of the Australian region, 

 though not at all known to-day, must have 

 been very analogous to and in part identical 

 with the Patagonian. 



The different adaptive radiations of orders 

 and families have given a very different as- 

 pect to the existing faunas of Australia and 

 Patagonia, in Australia only Monotremates 

 and Marsupials having survived, in Pata- 

 gonia principally histricomorph Eodents 

 and Edentata. The existing fauna of Aus- 

 tralia, New Guinea and other allied islands 

 has received by Miocene immigration some 

 placental mammalia, as Canis and Uromys 

 in Australia, Sus and Uromys in New 

 Guinea, and other genera in the Moluccas. 

 This proves that Australia and New Guinea, 

 at least during the Miocene, continued to 

 be connected with Asia as in the foregoing 

 periods. There existed therefore in the 



earlier Tertiary a continuous land masB 

 from Antarctica and Patagonia, via Aus- 

 tralia and Asia, to Europe and North Amer- 

 ica. This enormous territory, my Eurygsea, 

 was the birthplace of the placental mam- 

 mals. The Steuogsea (or Archheleuis) ex- 

 tending from tropical South America to 

 Africa, Madagascar and Bengal was in the 

 Eocene without mammals. 



It is certain that we have to-day no 

 knowledge at all of the Eocene mammals of 

 Australia, Brazil and Africa, but from the 

 facts given it seems to be highly probable 

 that future discoveries may confirm what 

 we expect. 



Paleophytical studies have given evi- 

 dence of a great resemblance between the 

 Cretaceous floras of North America and 

 Eurasia. According to Fr. Kurtz, the same 

 flora appears also at St. Cruz, Patagonia 

 em Cerro Guido (Revista Museu La Plata, 

 Vol. X., 1899, p. 43 ff.). According to the 

 facts given above, this flora cannot have 

 reached Patagonia from North America, as 

 the two Americas were then separated and 

 no South American continent existed. It is 

 also impossible to admit that a land bridge 

 formed by the Andes served for the migra- 

 tion, because these did not then exist, as the 

 Cretaceous marine beds of the Andes prove. 

 There must then have been a connection be- 

 tween the Antarctic Cretaceous continent, 

 the Archiuotis of the writer, and Asia. It 

 maybe observed that the genus Qiierctw was 

 represented in the Cretaceous beds of both 

 Patagonia and Australia, where to-day it 

 has no representative. What has occurred 

 in the case of Quercus and other genera in 

 both Australia and Patagonia and what is 

 observed in Patagonia with reference to 

 mammals may have happened also in Aus- 

 tralia to the earlier placental mammals. 

 Further, it must be remembered that Aus- 

 tralia, and South America also, developed 

 by coalescence of different parts, each of 

 which had its own history. 



