92 IOWA STUDIES IN NATURAL HISTORY 
The position of Barbados makes any collection from there 
important in the study of geographical distribution. The several 
elements that, taken together, form the comprehensive ‘‘An- 
tillean fauna’’ might be expected to find a common ground in 
Barbados. The northerly drift from the Brazilian coast should 
cause a certain Brazilian element in Tobago, Barbados and the 
line of islands north. This is the case only as to Barbados. The 
westerly drift from the Atlantic across the line of the Caribbees 
into the Caribbean (to pour out again in the great Gulf Stream) 
might be expected to convey the Barbadian mollusks to the 
shores of Central America and thence to Florida and the Gulf 
of Mexico. This is partially the case. From Barbados, as a 
sort of common station, we may trace two quite distinct ele- 
ments in the Antillean mollusk fauna and these might be desig- 
nated the Antillean island element and the Antillean continental 
element. The first contains less of the Brazilian influence and 
represents the true ‘‘Antillean’’ fauna (Lesser and Greater 
Antilles, Florida Keys, Bahamas, Gulf Stream to Hatteras) ; 
the second is a continuance of the Brazilian elements along the 
north shore of South America,—the Central American coast 
and Texas to the Mississippi River—though modified by inclu- 
sion of true Antillean species. 
In 86 fathoms, due west of the Cable Station, we obtained a 
single, but living, specimen of an Ovulum which is scarcely 
separable from the Ovulum carnea Poir, of the Mediterranean. 
This is the first record of a true Ovulum from the West Atlantic. 
The fact of its closeness, or even identity, with a Mediterranean 
species, is suggestive and interesting. The equatorial drifts 
from Africa to Brazil must have had some important bearing 
upon the Antillean marine fauna. There are many Mediter- 
ranean, East African and Antillean mollusks that show a rela- 
tionship, but none that according to modern acceptances of a 
‘“species’ are quite positively identical. The late Tertiary of 
Italy and the Mediterranean region does, however, contain a 
surprising number of species exceedingly closely allied with the 
living species in the West Indies, and one might almost say 
the origin itself of our Antillean fauna is found in the Pliocene 
of Southern Europe. The living Mediterranean fauna is less 
