344 SMITHSONIAN MISCELLANEOUS COLLECTIONS [von. 48 
siphonal lobe of the mantle with two appendicular lobes; verge large 
with an appendicular process; operculum usually absent; teeth of 
the radula usually in one tricuspid series. 
Subfamily CARICELLINZ 
Shell with the protoconch membranous and caducous within 
the ovicapsule; operculum absent; other characters much as in 
Voluta. The radula variable, sometimes absent. 
Subfamily VoLUTOMITRINZ 
Shell with protoconch minute (shelly?), the adult unicolor with 
a conspicuous periostracum ; small, boreal. Eyes on stalks adherent 
to and shorter than the tentacles; no epipodial lappets, no oper- 
culum, no siphonal lobes; radula of a single long series, the separate 
teeth unicuspidate with deeply arcuate bases. 
We may now consider the American species. 
At first one would hardly think of America as a metropolis of 
Volutes ; it is only when the scattered data are brought together, as 
in this paper, that it is practicable to realize that more than one 
third of all the known species, including Lyria and Eneta, occur 
on the coasts of America. 
There are enumerated in the present paper thirty-three species 
belonging to ten genera. With the exception of one Volutomitra 
common to the north of Europe, and the species of Voluta which 
reach the coast of West Africa, all the species are strictly American, 
the Falkland Islands being faunally a part of South America. Of 
the ten genera, only Voluta, Lyria and Volutomitra are represented 
elsewhere than on the coast of America. A study of our Tertiary 
Volutidz shows that all these groups originated in American waters, 
though some fossils like Eucymba and V olutocorbis are now extinct 
in their original region and represented in the recent fauna only 
by species of distant seas. The geographical grouping of genera 
will probably prove true for the species of other regions as it has 
here. 
The centers of distribution were evidently two; one near the 
southern end of South America and the other in the Antillean 
region. Omitting the boreal Volutomitra, only four species from 
the former center (three of them abyssal) and three from the 
latter (all species of Eneta) have reached the Pacific coast north 
of south latitude 40°. All of them are well differentiated from 
their Atlantic ancestors. A much more profuse Volute popu- 
