MOLLUSCAN AFFINITIES 
271 
Haiti and Mexico. The genus Gaeotis is quite confined to 
Portorico, while Amphibulima is limited to the Lesser 
Antilles.* 
All these studies yield the same fundamental results, 
namely, the presence within the Antillean area of an ex¬ 
tremely ancient stock distantly related to that of Central 
America and northern South America. After this fauna 
had developed to some extent, a widespread destruction 
apparently took place, due probably to submergence, fol¬ 
lowed by a reimmigration from the south and west. A 
more precise knowledge, however, of the minor physical 
changes which the West Indian islands have undergone 
can be acquired when we compare the results derived 
from the sedentary or slowly moving mollusks with those 
drawn from the more active members of the fauna. But 
there is one more element of importance in the Antillean 
molluscan fauna which has not yet been considered. It 
is especially in view of the remarks I made in the ninth 
chapter, on the striking relationship of the south-western 
American fauna to that of Europe, that I wish to direct par¬ 
ticular attention to the European affinities of the Antillean 
fauna. 
I think it was Dr. Kobelt f who first animadverted on the 
resemblance between the European molluscan fauna and that 
of the Antilles and Central America. At first sight, as ho 
remarks, the two faunas seem to be as distinct as any disciple 
of the principle of multiple centres of creation could wish. 
After a careful study, however, we certainly perceive distinct 
traces of relationship. The carnivorous snail Glandina, which 
is represented in the Mediterranean region of Europe by a 
single species, has its headquarters in the Antilles and in 
the surrounding States. It cannot be looked upon as a recent 
introduction to Europe, because its discontinuous range be- 
between the Caucasus and Algeria is altogether opposed to any 
such supposition. Several species of Glandina, moreover, 
occur in French and English Eocene, Oligocene and Miocene 
deposits, some of them being almost identical with still 
* Pilsbry, H. A., “Manual of Conchology,” Yols. X.—XII. 
f Kobelt, W., “ Verhaltniss d. Europaischen Landmolluskenfauna, &c.,” 
p. 145—14S. 
