PDF - Wallace Online

508 GEOGRAPHICAL ZOOLOGY. [iaut iv.
Family 4—CONID^. (3 Genera, 850 Species.)
DiSTKiBUTiON.— The Cones are universally distributed, but
this applies only to the genus Pleurotoma. Conus is tropical
and sub-tropical, and Githara is confined to the Philippine
Islands. There are about 460 fossil species, from the Chalk
formation to the most recent deposits.
Family 5.—VOLUTID^ (5 Genera, 670 Species.)
DiSTKiBUTiON.—The Volutes are mostly tropical ;
but a small
species of Mitra is found at Greenland, and a Marginella in the
Mediterranean. Cymla is confined to the West Coast of Africa
and Portugal. Valuta extends south to Cape Horn. There are
about 200 fossil species, from the Chalk and Eocene to recent
formations.
Family 6.—CYPP^IDiE. (3 Genera, 200 Species.)
Distribution.—The well-known Cowries are found all over
the world, but they are much more abundant in warm regions.
One small species extends to Greenland. There are nearly 100
fossil species, from the Chalk to the Miocene and recent forma-
tions.
Family 7.—NATICID^. (5 Genera, 270 species.)
Distribution.—The Naticidse, or Sea-snails, though most
abundant in the Tropics, are found also in temperate seas, and
far into the Arctic regions. Two other genera are fossil ; and
there are about 300 extinct species, ranging from the Devonian
to the Pliocene formations.