318 ISLAND LIFE part ii 



The Kev. John T. Gulick, who has made a special study of 

 the Achatinellinge, mforms us that the average range of the 

 species in this sub-family is five or six miles, while some 

 are restricted to but one or two square miles, and only 

 very few have the range of a whole island. Each valley, 

 and often each side of a valley, and sometimes even every 

 ridge and peak possesses its peculiar species.^ The island 

 of Oahu, in which the capital is situated, has furnished 

 about half the species already known. This is partly due 

 to its being more forest-clad, but also, no doubt, in part to 

 its being better explored, so that notwithstanding the 

 excejDtional riches of the group, we have no reason to 

 suppose that there are not many more species to be found 

 in the less explored islands. Mr. Gulick tells us that the 

 forest region that covers one of the mountain ranges of 

 Oahu is about forty miles in length, and five or six miles 

 in width, yet this small territory furnishes about 175 

 species of Achatinellidse, represented by 700 or 800 

 varieties. The most important peculiar genus, not belong- 

 ing to the Achatinella group, is Carelia, with six species 

 and several named varieties, all peculiar to Kaui, the most 

 westerly of the large islands. This would seem to show 

 that the small islets stretching westward, and situated on 

 an extensive bank with less than a thousand fathoms of 

 water over it, may indicate the position of a large sub- 

 merged island whence some portion of the Sandwich 

 Island fauna was derived. 



Insects. — Owing to the researches of the Rev. T. 

 Blackburn we have now a fair knowledge of the Coleop- 

 terous fauna of these islands. Unfortunately some of the 

 most jDroductive islands in plants — Kaui and Maui — were 

 very little exjDlored, but during a residence of six years the 

 equally rich Oahu was well worked, and the general 

 character of the beetle fauna must therefore be considered 

 to be pretty accurately determined. Out of 428 species 

 collected, many being obviously recent introductions, no 



1 Journal of the Linncan Society, 1873, p. 496, "On Diversity of 



Evolution under one set of External Conditions." Proceedings of the 



Zoolofjical Society of London, 1873, p. 80. "On the Classification of the 

 Achitinellidpe. " 



