[361] Pollonera, Boll. Mus. Zool. Torino, v. 1890, No. 87.
[362] South and south-western France, however, belong to the Mediterranean Sub-region.
[363] The coast-line of north-east China, including Corea and Japan to north Niphon, is much more definitely tropical than the adjacent inland districts. The coast-line, therefore, must be placed in the Oriental Region, while the inland districts belong to the Palaearctic Region.
[364] Biol. Centralbl. ii. p. 208.
[365] Craven, Journ. de Conchyl. (3) xxviii. p. 101.
[366] Jahrb. Deutsch. Malak. Gesell. viii. p. 278.
[367] Netchayeff, Kazan Soc. Nat. xvii. fasc. 5.
[368] Fauna der Congerien-Schichten, p. 142.
[369] Streptaxis is a remarkable instance of a mainland genus. Although abundant in the Oriental, Ethiopian, and Neotropical regions, it never seems to occur on any of the adjacent islands, except in the case of Trinidad (1 sp.), which is practically mainland. Omphalotropis, on the other hand, is the exact reverse of Streptaxis in this respect, occurring all over Polynesia and the Malay Is., as far west as Borneo, as well as on the Mascarenes, but never, save in a doubtful case from China, on the mainland of Asia, Australia, or Africa.
[370] The Amboyna group has been much the better explored. Common to both groups are one sp. each of Kaliella, Trochomorpha, Opeas, Leptopoma, Cyclotus, Helicina.