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Show 1 9 0 3 . ] GEOGRAPHICAL DISTRIBUTION OF SPIDERS. 3 6 7 Oligocene. At the present time the family is represented by Adonea and Dorceus in the southern area of the Mediterranean; by Dresser its and Seothyra in Tropical and South Africa; by Stegodyphus in the Mediterranean Region, India, Ceylon, and Burma in the Oriental Region, and East and South Africa in the Ethiopian Region ; by Eresus, which extends across Europe and Asia from England to China, being especially abundant in the Mediterranean Region and also occurs in South Africa. The absence of this group from Madagascar points to a late (probably Pliocene) incursion from the north into Africa, which, in conjunction with its failure to reach North America and Australia, also explains its absence from South America. The only existing genus of Urocteida?, Uroctea, was represented in the European Oligocene. At the present time it is found in the Mediterranean Region, China, Japan, India, and South Africa. The apparent absence of the genus from Madagascar indicates a late movement into South Africa. The Palpimanidae are also alleged to date back to the Oligocene. The most primitive member of the family, Huttonia, constituting the Huttoniinae, is now restricted to New Zealand. The more specialised Stenochilinae are confined to the Oriental Region, where they range from Bombay to the Philippines. The Palpi-maninae, the most specialised of the three, to which the Oligocene genus belongs, are represented by two groups, the Chedimeae and the Palpimanese. The latter, containing the single genus Palpi-manus, occurs in the Mediterranean Region, Western India, and East and South Africa ; the former is represented by Boagrus in the Malay Peninsula, Steriphopus in Ceylon, Sarascelis in the Malay Peninsula and tropical West Africa, Diaphorocellus in South Africa, and by Otiothops and Aniscedus in South America. The survival of the primitive type, Uuttonia, in New Zealand assigns great antiquity to this group. The Stenochilinae and Palpimaninae were perhaps evolved in South-eastern Asia and spread thence in a westerly direction, the more specialised Palpimaninae reaching Europe in the Oligocene and passing into Africa and thence to South America. The entire absence of Palpimaninae from North America and Australia, and the near relationship that obtains between the genera from South America and Tropical Africa, almost compels the belief that the former country received this element of its fauna from the latter. The Anyphaenidee are represented in the Oligocene beds of Europe and North America. At the present time, one genus only, Anyphcenoj, occurs in the temperate area of the Northern hemisphere of the Old World; the same genus also occurs in North America; while the remainder of the genera, sixteen or so in number, extend into South America, principally along the Andean chain as far south as Tierra del Fuego. These facts suggest that the group had its origin in North America, perhaps in Eocene times, crossed thence into Asia and Europe before or during the Oligocene, and, when North and South America were Proc. Z o o l. Soc.-1903, V o l . I. No. X X IV . 24 |