XVII NATURAL HISTORY 403 



became very oppressive. On two days the thermometer within 



the tent stood for some hours at 93"; but in the open air, in 

 the wind and sun, at only 85°. The sand was extremely hot ; 

 the thermometer placed in some of a brown colour immediately 

 rose to 137°, and how much above that it would have risen I 

 do not know, for it was not graduated any higher. The black 

 sand felt much hotter, so that even in thick boots it was quite 

 disagreeable to walk over it. 



The natural history of these islands is eminently curious, 

 and well deserves attention. Most of the organic productions 

 are aboriginal creations found nowhere else ; there is even a 

 difference between the inhabitants of the different islands ; yet 

 all show a marked relationship with those of America, though 

 separated from that continent by an open space of ocean, 

 between 500 and 600 miles in width. The archipelago is a 

 little world within itself, or rather a satellite attached to 

 America, whence it has derived a few stray colonists, and has 

 received the general character of its indigenous productions. 

 Considering the small size of these islands, we feel the more 

 astonished at the number of their aboriginal beings, and at 

 their confined range. Seeing every height crowned with its 

 crater, and the boundaries of most of the lava-streams still 

 distinct, we are led to believe that within a period, geologically 

 recent, the unbroken ocean was here spread out. Hence, both 

 in space and time, we seem to be brought somewhat near to 

 that great fact — that mystery of mysteries — the first appearance 

 of new beings on this earth. 



Of terrestrial mammals there is only one which must be 

 considered as indigenous, namely a mouse (Mus Galapagoensis), 

 and this is confined, as far as I could ascertain, to Chatham 

 Island, the most easterly island of the group. It belongs, as I 

 am informed by Mr. Waterhouse, to a division of the' family of 

 mice characteristic of America. At James Island there is a 

 rat sufficiently distinct from the common kind to have been 

 named and described by Mr. Waterhouse ; but as it belongs to 

 the old-world division of the family, and as this island has 

 been frequented by ships for the last hundred and fifty years, 

 I can hardly doubt that this rat is merely a variety, produced 

 by the new and peculiar climate, food, and soil, to which it has 



