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THE AMEBIC AN NATURALIST [Vol. XLIV 



in AYest Africa, namely, in the region south of Sene- 

 gambia; on the middle Niger River; in the southern 

 central Sahara and in northern Nigeria; in Togo and 

 Cameron (Gulf of Guinea) ; and even as far south as the 

 Gabun, Angola and Mossamedes. Although these de- 

 posits are rather scattered, their Mediterranean character 

 has been recognized, so that it appears as very probable 

 that they belong to a continuous sea, which extended 

 south from western Europe along the west African coast. 

 That is was actually continuous is demonstrated, accord- 

 ing to Stromer, by the distribution of the Nummulites 

 in these beds, which are found only in the north, and 

 indicate a cold northward current along the west African 

 coast: such a current could develop only under a similar 

 distribution of land as at present, namely, if the 

 west African coast extended uninterruptedly from south 

 to north, as it now does. This, of course, would show 

 that the Atlantic at that time existed approximately in 

 its present form, its northern (Tethys) and southern 

 (Nereis) parts being connected, and that the separating 

 laud liridgc, Arclilielenis, had disappeared. 



All the above considerations lead us only to one con- 

 clusion : that in the beginning of the Tertiary Archhelenis 

 had ceased to exist, and that there icas no connection any 

 more between South America and Africa. Indeed, the 

 facts introduced by von Ihering in support of his assump- 

 tion of the existence of this land-bridge in the Eocene, 

 prove to be, under renewed critical investigation, the 

 strongest evidence fur the contrary, and it has been shown 

 above that also some other facts, which apparently con- 

 tribute to the support of von Ihering 's view, may be 

 easily understood under the assumption that Archhelenis 

 had been destroyed at the beginning of the Tertiary 



