No. 520] TERTIARY ABCRHELENIS 241 



that a separation of the Patagonian and Chilean sea by 

 land is to be assumed for the explanation of the absence 

 of these tropical types in the Patagonian beds, as von 

 Ihering is inclined to do (p. 495). Of course, the Pata- 

 gonian beds were deposited on the east side, those of 

 Navidad on the west side, of the old peninsula extending 

 northward, and now represented by the Chilean Coast 

 Cordilleras, but this peninsula had an end somewhere to 

 the north, and around this point a communication of the 

 two seas was possible, till the elevation of the Cordil- 

 leras de los Andes took place, and connected the old 

 Chilean land with the land lying to the east of it. 



Further, if there was no connection of Africa and 

 Brazil any more in Tertiary times, the migration of the 

 Indo-European forms to Patagonia by the route indi- 

 cated above (East Africa, and south coast of Archhel- 

 enis) was impossible. Yet there is another way open. 

 As von Ihering points out (p. 81), this Indo-European 

 fauna reached eastward to Australia and the Pacific Is- 

 lands, and thus it very likely does not originally belong 

 to the fauna of the old Tethys (Mediterranean, North 

 Atlantic, West Indian seas), but consists of old Pacific 

 elements which extended, in the Tertiary, eastwards into 

 the Mediterranean part of the Tethys (Europe). The 

 very absence of these types in the West Indies and in 

 North America supports this view. And further, since 

 the Antarctic fauna, to which the Patagonian fauna 

 shows the closest affinities, is nothing but an offshoot of 

 the old Pacific fauna, the relations of the Patagonian to 

 the Indo-European forms find thus their explanation, 

 and the way, by which these faunas are connected, ap- 

 parently goes over Australia and Antarctica. 



Finaily, for the non-existence of Archhelenis in the 

 Eocene very recently a new line of evidence has been 

 introduced. Stromer 2 points out that recently quite a 

 number of marine Eocene deposits have been discovered 



2 Stromer, E., "Ueber Alttcrtiaer in Westafrika und die Suedatlantis, " 

 Jahrb. l-gl. Prcuss. Grnl. Lmuhsnnst.. 30. 1900, p. 511 ff. 



