CHAP. XTII,] 



THE GALAPAGOS ISLANDS. 



273 



The great difference presented by the birds of these islands 

 as compared with those of the equally remote Azores and 

 Bermudas, is sufficiently explained by the difference of climatal 

 conditions. At the Galapagos there are none of those periodic 

 storms, gales, and hurricanes which prevail in the North 

 Atlantic, and which every year carry some straggling birds of 

 Europe or North America to the former islands ; while, at the same 

 time, the majority of the tropical American birds are non-migra- 

 tory, and thus afford none of the opportunities presented by the 

 countless hosts of migrants which pass annually northward and 

 southward along the European, and especially along the North 

 American coasts. It is strictly in accordance with these different 

 conditions that we find in one case an almost perfect identity 

 with, and in the other an almost equally complete diversity from, 

 the continental species of birds. 



Insects and Land-sliells. — The other groups of land-animals 

 add little of importance to the facts already referred to. The 

 insects are very scanty ; the most plentiful group, the beetles, 

 only furnishing about thirty-five species belonging to twenty- 

 nine genera and eighteen families. The species are almost all 

 peculiar, as are some of the genera. They are mostly small 

 and obscure insects, allied either to American or to world-wide 

 groups. The Carabidse and the Heteromera are the most abun- 

 dant groups, the former furnishing six and the latter eight 

 species. 1 



1 The following list of the beetles yet known from the Galapagos shows 

 their scanty proportions and accidental character ; the thirty-seven species 

 belonging to thirty-one genera and eighteen families. It is taken from 

 Mr. Waterhouse's enumeration in the Proceedings of the Zoological Society 

 for 1877 (p. 81):— 



Caeabid^. 

 Feronia calathoides. 

 „ insularis. 

 „ galapagoensis. 



Malacoderms. 



Ablechrus darwinii. 

 Corynetes ruhpes. 

 Bostrichus imciniatiis. 



Amblygnathus obscuricornis. 

 Soleuophorus galapagoensis. 

 Notaphus galapagoensis. 



Lamelltcornes. 



Copris lugubris. 

 Oryctes galapagoensis. 



DYTiscm^E. 

 Eimectes occidentalis. 



Elaterid^:. 

 Pliysorhinus galapagoensis. 



T 



