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determination of the genera, but there can be little doubt that most of them represent important facts in distribution. The Nearctic region is comparatively poor in Carabidae. Its more important peculiar genera are, Dicaelus (22 sp.), Pasimachus (17 sp.), Eurytrichus (9sp.), Sphaeroderus (7 sp.), Pinacodera (6 sp.), and others of smaller extent, about 30 in all. It also possesses representatives of a considerable number of Palaearctic genera, as already indicated; and a few of South American genera, of which Helluomorpha and Galerita are the most important. The Neotropical region is very rich in peculiar forms of Carabidae, as in almost all other great groups. It possesses more than 100 peculiar genera, but about 30 of these are confined to the South Temperate sub-region. The more important peculiar genera of Tropical America are, Agra (144 sp.), Ardistomus (44 sp.), Schizogenius (25 sp.), Pelecium, (24 sp.), Calophena (22 sp.), Ctenodactyla (7 sp.). Among the Chilian and South Temperate peculiar forms are, Antarctia (29 sp.), Scelodontis (10 sp.), Tropidopterus (4 sp.). Among the Neotropical genera with outlying species are, Pachyteles (50 sp.), one of which is West African; Selenophorus (70 sp.), with 4 African, 4 Oriental, and 1 from New Caledonia; Ega (11 sp.), with one in the East Indies, and one in New Caledonia; Galerita, with 36 American species, 8 African, and 3 Indian; Callida and Tetragonoderus, mostly American, but with a few African, Oriental and Australian species; and Pseudomorpha, common to America and Oceania. The Australian region is almost equally rich, possessing about 95 peculiar genera of Carabidae, no less than 20 of which are confined to New Zealand. The most important are, Carenum, Promecoderus, Scaraphites, Notonomus, AEnigma, Sphallomorpha, Silphomorpha, and Adelotopus. The gigantic Catadromus has 4 Australian species and 1 in Java; Homalosoma has 31 species in Australia and New Zealand, and 1 in Madagascar. Celebes and New Guinea have each peculiar genera, and one is common to Australia and the Cape of Good Hope. The Oriental region possesses 80 peculiar genera, 10 of which are confined to Ceylon. The more important are, Pericallus, Planetes, and Mormolyce. Distrigus is also characteristic of this region, with one species in Madagascar; while it has Orthogonius, Hexagonia, Macrochilus, and Thyreopterus in common with the Ethiopian region, and is rich in the fine tropical genus, Catascopus. The Ethiopian region has 75 peculiar genera, 8 of which are confined to Madagascar. The more important are, Polyhirma, Graphipterus, and Piezia. Anthia is chiefly African, with a few species, in India; Abacetus is wholly African, except a species in Java, and another in South Europe; and Hypolithus is typically African, but with 7 species in South America and 1 in Java. The facts of distribution presented by this important family, looked at broadly, do not support any other division of the earth into primary regions than that deduced from a study of the higher animals. The amount of speciality in each of these regions is so great, that no two of them can be properly united; and in this respect the Carabidae accord wonderfully with the Vertebrates. In the details of distribution there occur many singular anomalies; but these are not to be wondered at, if we take into consideration the immense antiquity of Coleopterous insects—which existed under specialised forms so far back as the Carboniferous epoch,-the ease with which they may be dispersed as compared with larger animals, and the facilities afforded by their small size, habits of concealment, and often nocturnal habits, for adaptation to the most varied conditions, and for surviving great changes of surface and of the surrounding organic forms. The wonder rather is, not that there are so many, but so few cases of exceptional and anomalous distribution; and the fact that these creatures, so widely different from Vertebrates in organisation and mode of life, are yet on the whole subject to the same limitations of range as were found to occur among the higher animals, affords a satisfactory proof that the principles on which our six primary regions are founded, are sound; and that they are well adapted to exhibit the most interesting facts of geographical distribution, among all classes of animals. Much stress has been laid on the fact of a few species of such typical European genera as Carabus, Dromius, and others, being found in Chili and Temperate South America; and it has been thought, that in a system of Entomological regions this part of the world must be united to the Northern Hemisphere. But these writers omit to take into account, either the large numbers of isolated and peculiar forms characteristic of South Temperate America, or the indications of affinity with Tropical America and Australia, both of which are really more important than the connection with Europe. The three important Chilian genera, Cascelius, Barypus, and Cardiopthalmus, are closely allied to the Australian Promecoderus ; others, as Omostenus and Plagiotelium, are quite isolated; while Antarctia and Metius, according to Lacordaire, form a distinct division of the family. Chili, too, has many species of Pachyteles, Coptodera, and other South American genera; and this affinity is far stronger in many other families than in the Carabidae. The existence of representatives of typical northern forms in Chili, is a fact of great interest, and may be accounted for in a variety of ways; (see Vol. II. p. 44) but it is not of such a magnitude as to be of primary importance in geographical distribution, and it can only be estimated at its fair value, by taking into account the affinities of all the groups inhabiting that part of the world.
LUCANIDAE. (45 Genera, 529 Species.)
Passing over a number of obscure families, we come to the remarkable group of the Lucanidae, or Stag-beetles, which, being almost all of large size, and many of them of the most striking forms, have been very thoroughly collected and assiduously studied.
The most curious feature of their general distribution, is their scarcity in Tropical South America, and their complete absence from Tropical North America and the West Indian Islands, though they appear again in Temperate North America. In the New World they may, in fact, be looked upon as a temperate group characteristic of the extra-tropical regions and the highlands; while in the Old World, where they are far more abundant, they are distinctly tropical, being especially numerous in the Oriental and Australian regions. No genus has the range of the whole family, Dorcus and Lucanus being absent from Africa, while Cladognathus is unknown in the New World and on the continent of Australia. The Oriental region is the richest in peculiar forms, possessing 16 genera, 7 of which are wholly confined to it, while 3 others only just range beyond it to North China on the one side, or to the Austro-Malayan islands on the other. The Australian region comes next, with 15 genera, of which 7 are wholly peculiar. South America has 12 genera, 10 of which are peculiar. The Ethiopian region has 10 genera, 7 of which are peculiar, and 2 of these are confined to the island of Bourbon. The Palaearctic region has 8 genera, and the Nearctic 5; one genus being peculiar to Europe, and two confined to Europe and North America. The Ethiopian and Oriental regions have 3 genera in common and peculiar to them; the Oriental and Australian 3; while the Australian and Neotropical have 1 in common, to which may be added Streptocerus, which represents in Chili the Australian Lamprima. Among the special features presented by the distribution of the Lucanidae, may be mentioned—the remarkable group of genera, Pholidotus, Chiasognathus, and Sphenognathus, confined to Temperate South America, the Andes, and-mountains of Brazil; Lucanus (19 sp.), almost confined to the Oriental and Palaearctic regions, three species only inhabiting North America; Odontolabris (29 sp.), wholly Oriental, with 2 sp. in Celebes; Nigidius (11 sp.), Ethiopian, but with species in Formosa, the Philippines, and Malacca; Syndesus (11 sp.), common to Australia, New Caledonia, and South America; Figulus (20 sp.), divided between Africa and Madagascar on the one hand, and Australia, with the Malay and Pacific Islands, on the other. The facts of distribution here sketched out are in perfect accordance with those of many groups of Vertebrates. The regions are sharply contrasted by their peculiar and characteristic genera; the several relations of those regions are truly indicated; while there is a comparatively small proportion of cases of anomalous or eccentric distribution.
CETONIIDAE (120 Genera, 970 Species)
As representative of the enormous group of the Lamellicorns, which, according to continental entomologists, forms a single family numbering nearly 7,000 species, we take the Cetoniidae or Rose-Chafers. These comprise a number of the most brilliant and beautifully-coloured insects, including the gigantic Goliathi, which are among the largest of known beetles. They have been assiduously collected in every part of the world, and their classification has been elaborated by many of our most eminent entomologists.
The Cetoniidae are especially abundant in tropical and warm countries, yet far more so in the Old World than in the New; and in the Old World, the Ethiopian region exhibits a marvellous richness in this family, no less than 76 genera being found there, while 64, or more than half the total number, are peculiar to it. Next in richness, though still very far behind, comes the Oriental region, with 29 genera, 17 of which are peculiar. The Neotropical has only 14 genera, but all except two are peculiar to it, and one of these is not found out of the New World. The Australian region has 11 genera, three only being peculiar. The Palaearctic region has 13, with 4 peculiar; the Nearctic 7, with 2 peculiar. The affinities of the regions for each other, as indicated by the genera confined to two adjacent regions, are in this family somewhat peculiar. The Ethiopian and Oriental show the most resemblance, 6 genera being common and peculiar to the two; the Oriental and the Australian are unusually well contrasted, having only one genus exclusively in common, while 8 genera are found in the Indo-Malay Islands which do not cross the boundary to the Austro-Malayan division, and several others only pass to the nearest adjacent islands; on the other hand, the only large Australian genus, Schizorhina, is found in many parts of the Moluccas, but not further west. The Australian and Neotropical regions exhibit no direct affinity, the nearest ally to the South American Gymnetidae being Clinteria, an African and Asiatic genus; while not a single genus is common