_Insects._--Owing to the researches of the Rev. T. Blackburn we have now a fair knowledge of the Coleopterous fauna of these islands. Unfortunately some of the most productive islands in plants--Kaui and Maui--were very little explored, 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 {319} less than 352 species and 99 of the genera appear to be quite peculiar to the archipelago. Sixty of these species are Carabidae, forty-two are Staphylinidae, forty are Nitidulidae, twenty are Ptinidae, twenty are Ciodidae, thirty are Aglycyderidae, forty-five are Curculionidae, and fourteen are Cerambycidae, the remainder being distributed among twenty-two other families. Many important families, such as Cicindelidae, Scaraboeidae, Buprestidae, and the whole of the enormous series of the Phytophaga are either entirely absent or are only represented by a few introduced species. In the eight families enumerated above most of the species belong to peculiar genera which usually contain numerous distinct species; and we may therefore consider these to represent the descendants of the most ancient immigrants into the islands. Two important characteristics of the Coleopterous fauna are, the small size of the species, and the great scarcity of individuals. Dr. Sharp, who has described many of them,[74] says they are "mostly small or very minute insects," and that "there are few--probably it would be correct to say absolutely none--that would strike an ordinary observer as being beautiful." Mr. Blackburn says that it was not an uncommon thing for him to pass a morning on the mountains and to return home with perhaps two or three specimens, having seen literally nothing else except the few species that are generally abundant. He states that he "has frequently spent an hour sweeping flower-covered herbage, or beating branches of trees over an inverted white umbrella without seeing the sign of a beetle of any kind." To those who have collected in any tropical or even temperate country on or near a continent, this poverty of insect life must seem almost incredible; and it affords us a striking proof of how erroneous are those now almost obsolete views which imputed the abundance, variety, size, and colour of insects to the warmth and sunlight and luxuriant vegetation of the tropics. The facts become quite intelligible, however, if we consider that only {320} minute insects of certain groups could ever reach the islands by natural means, and that these, already highly specialised for certain defined modes of life, could only develop slowly into slightly modified forms of the original types. Some of the groups, however, are considered by Dr. Sharp to be very ancient generalised forms, especially the peculiar