56 MANUAL OF THE MOLLUSCA. 
originally belonged. And when species occur both recent and 
fossil it is easy to perceive the direction in which their migra- 
tions have taken place. 
The Fauna of the Mediterranean has been critically examined 
by Prof. Forbes and M. Philippi, with this result,—that a large 
proportion of its population has migrated into it from the At 
lantic, and a smaller number from the Red Sea, and that the 
supposed peculiar species are diminishing so rapidly with every 
new research in the Atlantic, that it can no longer rank as a 
province distinct from the Lusitanian. 
When the Faunas of the other regions have been tested in 
the same manner, and disentangled, the result will probably be 
the establishment of a much greater number of proyinces than 
we have ventured at present to indicate on the map. 
It may be desirable to notice here the extraordinary range 
attributed to some of the marine species. These statements 
must be received with great hesitation; for when sufficiently 
investigated, it has usually proved that some of the localities 
were false, or that more than one species was included. The 
following are given by Dr. Krauss in his excellent monograph 
of the South African Mollusca :— 
Ranella granifera : Red Sea, Natal, India, China, Philippines, 
New Zealand. 
Triton olearius : Brazil, Mediterranean, Natal, Pacific. 
Purpura lapillus: Greenland, (Senegal, Cape). 
Venus verrucosa: (W. Indies), Brit. Senegal, Canaries, 
Mediterranean, Red Sea, Cape (Australia). 
Octopus vulgaris: Antilles, Brazil, Europe, Natal, Mauritius, 
India. 
Argonauta argo: (Antilles), Medit., Red Sea, Cape. 
LIucina divaricata is said to be ‘‘ found on the shores of Europe, 
India, Africa, America, and Australia.” (Gray.) In this case 
several species are confounded. The rock-boring Saxicava has 
been carried to all parts of the world in ballast, and it remains 
yet to be ascertained whether the same species occurs in a lying 
state beyond the Arctic Seas and North Atlantic. 
Lastly, the money cowry is always catalogued as a shell of the 
Mediterranean and Cape, although its home is in the Pacific, 
and it has no other origin in the Atlantic than the occasional 
wreck of one of the ships in which such yast quantities of the 
little shell are annually brought to this country to be exported 
again to Africa, 
