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Show 286 ISLAND LlFE. [l'AH'l' II. goats, and that iu consequence the cost of importing fuel for government use was 2,729l. 7s. ·8d. for a single year! About this time large numbers of European, American, Australian, and South African plants were imported, and many of these ran wild and increased so rapidly as to drive out and exterminate much of the relics of the native flora; so that now English broom gorse and brambles, willows and poplars, and some common American Cape and Australian weeds, alone meet the eye of the onlin;ry visitor. These, in Sir Joseph Hooker's opinion, render it absolutely impossible to restore the native flora, which only lingers in a few of the loftiest ridges and most inaccessible precipices, and is rarely seen except by some exploring naturalist. This almost total extirpation of a luxuriant and highly peculiar vegetation must inevitably have caused the destruction of a considerable portion of the lower animals which once existed on the island, and it is rather singular that so much as has actually been discovered should be left to show us the nature of the aboriginal fauna. Many naturalists have made small collections during short visits, but we owe our present complete knowledge of the two most interesting groups of animals, the insects, and the land-shells, mainly to the late l\1r. T. Vernon \Vollaston, who, after having thoroughly explored Madeira and the Canaries, undertook a voyage to St. Helena for the express purpose of studying its terrestrial fauna,, and resided for six months (1875-76) in a high central position, whence the loftiest peaks could be explored. The results of his labours are contained in two volumes, 1 which, like all that he wrote, are models of accuracy and research, and it is to these volumes that we are inuebted for the interesting and suggestive facts which we here lay before our readers. Insects-ColeopteTa.-The total number of species of beetles hitherto observed at St. Helena is 203, but of these no less than seventy-four are common and wide-spread insects, which have certainly, in Mr. Wollaston's opinion, been introduced by human agency. There remains 120 which aTe believed to be 1 Coleoptera Sanclw llele11ce, 1877; Teslacea Atlantica, 1878. CILAI'. XlV.] S'l'. HELENA. 287 tmly a,borigines, Hud of these all but one are found nowltere cl:-e on the globe. But in aduition to this large amount of specific pccnliar]ty (perhaps unequalled anywhere else in the world) tlte beetl s of this island are equally romarlmble for their generic isolation, and for the altogether exceptional proportion in which the great divisions of the order arc represented. The l'pecjcs belong to thirty-nine genera, of which no less than twenty-five n,rc pocuhnr to the island; and many of these are such isolateu forms tl1:~t it is imposs]ble to find their allies in any particular country. Still more remarkable is the fact, that more than two-thirds of the whole number of indigenous species are Rhyncophora or weevils, while more than two-fifths (fiftyfour species) belong to one family, tho Cossonidre. Now ~~lthough tlte Hhyncophora arc an immensely numerous group and always form a large portion of the insect population, they now here lse approach such a proportion as this. For example, in Madeirn they form one-sixth of the whole of the indigenous Uolcoptcra, in the Azores less than one-tenth, and in Britain one-seventh. Even more interesting is the fact that the twenty genera to which tl10se insects belong are every one of ·them peculiar to the isla.nd, and in many cases have no near allies els where, so tl:tat we cannot but look on this group of beetles fiS forming the most chamctcristic portion of the ancient insect fauna. Now, as the great majority of these are wood borers, and all arc closely attached to vegetation, and often to particular species of plants, we might, as Mr. Wollaston well observes, deduce the former luxuriant vegetation of the island from the great preponderance of this group, even had we not positive evidence that it was at no distant epoch densely forestdad. We will now proceed briefly to indicate the numbers and peculiarities of each of the families of beetles which enter into the St. Helena fauna, taking them, not in systematic order, but according to their importance in tl1e island. 1. RHYNCOP.HORA.-This great division includes the weevils and allied groups, and, as above stated, exceeds in number of species all the other beetles of the island. Four families are represented; the Cossonidre, with fifteen peculiar genera comprising fifty-four spocies, and one minute insect (Stenoscel'io hylastoides) |