PHYSICAL CONDITIONS— POSTGLACIAL. 533 



that the continental species of plants — those which nourished 

 most luxuriantly during the dry periods — have again begun to 

 extend themselves. 



To what extent the geography of Southern Europe was 

 affected in postglacial times there is no evidence, so far as I 

 know, to indicate. Some of the proofs of recent submergence 

 and emergence upon the coasts of the Mediterranean may 

 possibly be contemporaneous with those evidences of elevation 

 and depression which are so marked in North-western Europe, 

 but to what extent this may be the case I cannot even con- 

 jecture. The facts have never been systematically collected 

 and compared, and considerable complication arises from the 

 circumstance that the oscillations of level appear often to have 

 been comparatively local, as might have been expected would 

 be the case in a region where the volcanic forces continue to 

 show some activity. The land-connections that formerly joined 

 Europe to Africa probably disappeared in late glacial times. 

 We have no evidence, at all events, to show that they endured 

 down to the postglacial period. Thus, it would seem that the 

 most interesting and striking traces of postglacial climatic and 

 geographical changes are in large measure confined to North- 

 western Europe. We must not forget, however, that such 

 climatic changes as we have passed in review would be much 

 less strongly marked in lower latitudes than our own. The 

 farther south we go upon the Continent, the less likely are we 

 to come upon conspicuous evidence of postglacial mutations of 

 climate. It does not follow, however, that because such evidence 

 has not yet been detected in Southern Europe, it does not exist. 

 It will possibly be hard to find, and should it eventually be 

 discovered it will be botanists and zoologists rather than geolo- 

 gists that we shall have to thank for the discovery. The carrying 

 on of the tale of postglacial changes must indeed be resigned 

 to the former, for notwithstanding all that has been done in the 

 study of geographical botany and zoology, much yet remains to 

 be accomplished to clear up the obscurities which still becloud 

 the latest phases of geological history, and doubtless a promising 



