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Show 288 ISLAND LIFE. [PART 11. forming a peculiar genus, but which.has b~en found also at ~h~ Cape of Good Hope. It is therefore Impossible to say of whiC country it is really a native, or wheth er I· t 1· s m· d1' gen ous to. bot.h ' and dates back to the remote period when St. Helena recei~ed Its early emigrants. All the Cossonidre are fou~d in the .hlghe:cst and wildest parts of the island where the native veget~twn still lingers, and many of them are only found in ~he decaymg ste~s of tree-ferns, box-wood, arborescent Compositre, and o~her mdigenous plants. They are all . pre-emine~tly pecuh~r and isolated havino- no direct affimty to speCJes found m any other c~untry. 0 The next family, the Tanyrh~nchidre, .has one peculiar genus in St. Helena, with ten speCies. Th.Is genus (N esiotes) is remotely allied to European, Australian, a~d Madeiran insects of the same family : the habits of the speCies are similar to those of the Cossonidre. The Trachyphlmidre are represented by a. single species belonging to a pec~l~ar gen~u; not very remote from a European form .. The A:-nthnb1dre. agam are highly peculiar. There are twenty-six speCies. belongmg to three genera, all endemic, and so extremely peculiar that the.y form two new subfamilies. One of the genera, Acarodes, IS said to be allied to a Madeiran genus. 2. GEODEPHAGA.-These are the terrestrial carnivorous beetles, very abundant in all parts of the world, especially in the temperate regions of the northern hemisphere. In St. Helena there are fourteen species belonging to three genera, one of which is peculiar. This is the HaplothoTax buTcheltii, the largest beetle on the island, and now very rare. It resembles a large black Carabus. There is also a peculiar Calosoma, very distinct, though resembling in some respects certain African species. The rest of the Geodephaga, twelve in number, belong to the wide-spread genus Bembidium, but they are altogether peculiar and isolated, except one, which is of European type, and alone has wings, all the rest being wingless. . 3. HETEROMERA.-This group is represented by three pecuhar genera containing four species, with two specie.s. belongin~ to European genera. They belong to the fam1hes Opatndm, Mordellidre, and Anthicidm. 4. BRACHYELYTRA.-Of this group there are six peculiar • CHAP. XIV.] ST. HELENA. 289 species belonging to four European genera-Homalota, Phi!onthus, Xantholinus, and Oxyte]us. 5. PRIOCEL~ATA.-The families Elateridw and Anobiidm are each represented by a peculiar species of a European genus. 6. PHYTOPHAGA.-There are only three species of this tribe belonging to the European genus Longitarsus. ' 7. LAMELLICORNis.-Here are three species belonging to two genera. One is a peculiar species of Trox, allied to South African forms ; the other two belong to the peculiar genus Melissius, which Mr. Wollaston considers to be remotely allied to Australian insects. 8. PsEUDO-TRIMERA.-Here we have the fine lady-bird Chilo? nenus lunata, also found in Afric~, but apparently indigenous in St. Helena ; and a peculiar species of Euxestes, a genus only found elsewhere in Madeira. D. TnrcnOPTERYGIDlE.-These, the minutest of beetles, are represented by one species of the European and Madeiran genus Ptinella. 10. NECROPHAGA.-One indigenous species of Cryptopha.ga inhabits St. Helena, and this is said to be very closely allied to a Cape species. PeculiaTitics and Origin of the Coleoptera of St. IlelenCt/.-W e• see that the great mass of the indigenous species are not only peculiar to the island, but so isolated in their characters as to show no close affinity with any ex~sting insects; while a small number (about one-third of the whole) have some relations, though often very remote, with species now inhabiting Europe, Madeira, or South Africa. These facts clearly point to the very great antiquity of the insect fauna of St. Helena, which has allowed time for the modification of the originally introduced species, and their special adaptation to the conditions prevailing in this remote island. This antiquity is also shown by the remarkable specific modification of a few types. Thus the whole of the Cossonidre may be referred to three types, one species only ( Hexacoptus feT?'~tgine'ns) being allied to the European Cossonidre though forming a distinct genus; a group of three genera and seven species remotely allied to the Stenoscelis hylastoides, which occurs also at the Cape; while a group of twelve genera with u |