THE LUSITANIAN FAUNA. 289 



imply that it is gradually withdrawing towards its 

 centre of origin from a former wider range. Such 

 an eventuality, as we have seen, has actually taken 

 place in a great number of instances. 



It is not only in the British Islands that we 

 perceive the influence of the Lusitanian element. 

 Scandinavia, Russia indeed almost every part of 

 Europe can boast of some migrants which have 

 originated in South-western Europe or on the 

 mysterious lands which lay beyond it. As a rule, 

 however, we notice a marked decrease of Lusitanian 

 species as we travel eastward from Western Europe. 

 Nevertheless, certain forms have travelled far beyond 

 the confines of our continent, and we certainly meet 

 with them in Asia and Northern Africa. 



It is remarkable that we are apt to mistake some- 

 times for Lusitanian migrants species which are of 

 Oriental origin. In a previous paper I classed such 

 animals which had apparently originated in South- 

 western Europe, but had really come from Asia by a 

 circuitous southern route, with the Lusitanians. How- 

 ever, there is really no reason why the two should 

 not be kept apart, provided we can discriminate 

 between the pseudo-Lusitanians and the true ones. 

 I have already indicated in the last chapter how 

 these pseudo-Lusitanian migrants originated. 



Supposing an Oriental species had left Asia for 

 Europe in miocene times, it would on its arrival in 

 Greece have had to decide between two courses. It 

 could either advance into the newly-formed Alpine 



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