THE GLACIAL EPOCH. 41 



There remains the difficult question whether the embouchure of the Baltic opened into the 

 Atlantic between Iceland and the British Islands, or between Spitzbergen and Fiumark ; in other 

 words, whether Greenland was united to Europe by Norway, or by Britain. As Iceland, Greenland, 

 and Spitzbergen, were united, the Baltic must have reached the sea by one or other of the above 

 passages. 



I have tried to make out something from a comparison of the phaenogamic flora of Great Britain, 

 and of the Scandinavian Peninsula, with that of Greenland. I thought that it might show traces of 

 its former connexion by an imdue preponderance of anj' peculiarity existing in the one flora or the 

 other ; but they have turned out so equally balanced, that no inference, one way or the other, could 

 be drawn from the contrast.* 



It is therefore very much a matter of imagination which supposition we adopt. I prefer the 

 union with Britain for the following fancies, I can scarcely call them reasons. 1. It carries on the 

 land in the same line in which what we see of it is already directed. 2. There are a number of 

 stepping-stones on the way which may be supposed to indicate the topmost summits, and the 

 course of the sunken land ; and 3. It allows the prolongation of the Baltic to pursue its course 

 to the open sea in a straight line instead of turning it off a second time at right angles. 



The proof that Greenland was united to Europe subsequently to the glacial epoch, is thus clear 

 enough. That the communication between Europe and America also subsisted for a short time, 

 although probably imperfect and interrupted, seems also pretty plain ; it is more difficult to 

 judge whether that communication still subsisted after the separation between these lands took 

 place. The fact that Iceland is wholly destitute of aboriginal mammals, except perhaps what 

 may prove to be an American Lemming, and that those of Greenland and Spitzbergen are not 

 of the European, but American type, shows that the connexion between Europe and them, while 

 it endured long enough to allow them to be peopled by European plants and European insects, 

 was severed before mammals followed on their trace. The connexion with both continents may 

 then have been severed, for although the mammals in Greenland are of the American tj-pe, they 

 are very {cw, and all of a class that might have migrated across any moderate distance of ice; and 

 Spitzbergen and Iceland may have continued united to Greenland after both were disunited 

 from the rest of Europe. In any view it is only the now submerged north-western portion of 

 miocene Europe, which still subsisted dnring and after the glacial epoch. Its south-western part 

 cannot have done so, or we should have had a flora in Europe more nearly resembling that of 

 North America. Some remains of it, however, still survive, to show that the miocene flora escaped, 

 where it was beyond the influence of the cold. 



I may remark, par parenthese, here, that it would be difficult to find two lands better adapted for 

 illustrations of 'Mr. Darwin's views of colonization by flotsam and jetsam than Spitzbergen and 



* I took the Greenland flora from the tables in Hooker's siderably greater than those in Britain, the numbers being 



ussay above mentioned ; the Scandinavian from Frie's 1708 Scandinavian plants against 1239 British, conse- 



"SummaVegetabilium Scandinavia;," and the British from quently the former might be expected to possess the 



Bentham's " Hand Book " (as steering a just medium be- largest actual number of species ; tried according to that 



tween the extreme opinions regarding species on both ratio, the proportion of Greenland plants to the whole of 



sides), and this comparison gives 232 Greenland species the Scandinavian is a little more than a seventh (about 



as found in the Scandinavian Peninsula, and only 167 in 7|), while that of Britain is also a little more than a 



Britain, but this apparent preponderance in favour of seventh (about 73), showing that the difference is too 



Scandinavia is neutralised by the fact that the number of slight to allow us to draw any conclusions from it cither 



species inhabiting the Scandinavian Peninsula is con- one way or other. 



G 



