396 



GALAPAGOS ARCHIPELAGO. 



[CHAP. xvn. 



Hence we have the truly wonderful fact, that in James Island, 

 of the thirty-eight Galapageian plants, or those found in no 

 other part of the world, thirty are exclusively confined to this 

 one island ; and in Albemarle Island, of the twenty-six abori- 

 ginal Galapageian plants, twenty-two are confined to this one 

 island, that is, only four are at present known to grow in the 

 other islands of the archipelago ; and so on, as shown in the 

 ^bove table, with the plants from Chatham and Charles Islands. 

 This fact will, perhaps, be rendered even more striking, by 

 giving a few illustrations : thus, Scalesia, a remarkable arbo- 

 rescent genus of the Compositse, is confined to the archipe- 

 lago : it has six species ; one from Chatham, one from Albe- 

 marle, one from Charles Island, two from James Island, and the 

 sixth from one of the three latter islands, but it is not known 

 from which : not one of these six species grows on any two 

 islands. Again, Euphorbia, a mundane or widely distributed 

 genus, has here eight species, of which seven are confined to the 

 archipelago, and not one found on any two islands : Acalypha 

 and Borreria, both mundane genera, have respectively six and 

 seven species, none of which have the same species on two islands, 

 with the exception of one Borreria, which does occur on two 

 islands. The species of the Composite are particularly local ; 

 and Dr. Hooker has furnished me with several other most st/ik- 

 ing illustrations of the difference of the species on the different 



