MR. BUNBURY ON THE BOTANY OF MADEIRA. 10 



intervening. This remark applies, of course, equally, whether we 

 suppose species to haA^e migrated from Europe to the islands, or 

 from the islands to Europe. There are instances in wliich the 

 latter supposition seems the more probable, Erica arhorea^ for 

 example, though Avidely spread through the south of Europe, 

 nowhere (I believe) predominates so remarkably, or grows to so 

 extraordinary a size, as in Madeira and the Cauaries; whence one 

 is tempted to conclude, that these islands were its true original 

 native country. It is doubtless within the limits of possibility, 

 that the small seeds of this plant may have been transported by 

 violent winds across the intervening sea ; but the migration would 

 be much more easily explained on the hypothesis of a former land 

 communication. 



On the other hand, there are botanical anomalies difficult to 

 explain on this supposition. One would have expected, if such a 

 communication had existed, that the plants common to Europe and 

 Madeira would have been more particularly those of the iccst of 

 Europe ; whereas, in fact, the great majority of them are species 

 general through the Mediterranean region ; and few, if any, of the 

 more characteristic plants of Spain and Portugal occur in Madeira. 

 In particular, that island seems entirely to want the Cisttcs ladani- 

 fents (which is described as covering leagues and leagues of country 

 in Portugal), and indeed all the Cisti, as well as Erica ciliaris, 

 Erica vagans, and a great number more of the most characteristic 

 are^^European species. Dr. Hooker* has already remarked the 

 singular fact, that out of the 480 European species common to 

 Madeira, only 170 are found in the neighbourhood of Gibraltar, 

 although this latter locality has as many as 456 indigenous plants, 

 It is puzzling to imderstand how so many of the 480 (most of them 

 common South-Europe plants), in their supposed migration from 

 Europe to Madeira, or vice versa, should have missed Gibraltar. 



Again, one of the prominent botanical characters of the south 

 of Europe is the great number and variety of O^^ry^^^, especially 

 of the genera Orchis and Ophrys. A striking contrast in this 

 respect is presented by the Macaronesian groups, which are re- 

 markably poor in Orchids. Supposing a former connexion by 

 intervening land, one would have expected to meet with many 

 European species of this, as of other families. 



On the whole, I can hardly say that the botanical evidence 

 afforded by Madeira, and the other groups in question, in their 

 present state, gives very decisive support to the theory of an 



London 



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