1903. Prakgkr. — 17 ish Topographical Bota7iy, 39 



coast, and even " Germanic " plants — the most restricted type 

 of all — may be seen in western counties. Possibly Mr. 

 Colgan looks with marked disfavour on so broad a classifi- 

 cation of our plants — but for myself, if I sin, I am well content 

 to sin in so good company. If the broad view for which I 

 have contended be applied to the lists of species set down 

 under each of my types of distribution, and to Mr. Colgan's 

 revision of them, I do not fear that my conclusions will be 

 seriously imperilled. 



So much for the general theory of the grouping of the flora 

 under types, and its application. Another important and 

 highly controversial question on which Mr. Colgan touches 

 is the origin and history of our flora, where he attributes 

 *' oversight " and "confusion of thought " to my remarks on 

 the Glacial epoch and its passing away in relation to the flora. 

 On referring to the passage, 1 cannot detect any such features ; 

 but if there be, I fanc}^ that, at least, I am not alone in these 

 respects. My critic announces — with a confidence that geo- 

 logists will envy — that the ground " at the close of the Glacial 

 period was quite naked, a veritable tabula rasa from the bota- 

 nical point of view." But in Introduction to Cybele Hibemica, 

 p. xliv., the same writer states, with much reason, "" we are 

 hardly justified in supposing the glaciation of Ireland to 

 have completely denuded the country of its plant population," 

 and goes on to suggest the present condition and flora of 

 Greenland as fairly representing what obtained in Ireland 

 during the Glacial period. Now, the present flora of Green- 

 land numbers, according to the latest authority^, 386 species of 

 flowering plants — a curious kind of botanical tabula rasa I I 

 agree with Mr. Colgan in his earlier, not his later view, and 

 it was to such a vegetation that I referred when I spoke of a 

 "presumably weaker flora which was in possession of 

 the ground " which is the statement which Mr. Colgan describes 

 as an oversight. To judge from my critic's objection to my 

 phrase " successive waves of plant migration," it would appear 

 that his conception is that the Glacial period left the land abso- 

 lutely bare, and, hey presto ! our present flora took possession 



"• Warming : Ueber Grbulaud's Vegetation. Engler's Bot.Jahrb, x., 364 

 et seq. 



