
.594 OUR COMMON FRESH-WATER SHELLS. 
vipara subpurpura Say, Plate 9, fig. 8, has an oblong, 
subovate shell, olivaceous in color, with a tinge of purple. 
Figs. 9 and 10 represent younger specimens. Mr. Binney 
says he has traced this species from Texas through Louisiana 
and Mississippi to Key West, Fla., and in the Western 
States of Indiana, Wisconsin, and Missouri. 
V. contectoides W. G. Binney, Pl. 9, figs. 5, adult ; 6 and 7, 
young. The shell of this species is ornamented with four re- 
volving bands, is quite smooth and shiny, and the umbilicus is 
open. The shell closely resembles a common European spe- 
cies. Found in nearly all the Southern and Western States. 
Vivipara Georgiana Lea, Plate 9, figs. 1 and 15, oper- 
culum. This species inhabits Florida, Georgia, South Caro- 
TEN lina and Alabama. There are 
other species of this genus in 
the United States, but it was 
our intention to mention only 
those that were more charac- 
teristic. 
Of Melantho we have sever- 
al well marked species, among 
which Melantho ponderosa Say 
(Plate 9, figs. 14 and 16, 
young ; figs. 19 and 20, adult), 
is the largest. It is a heavy solid shell an inch and a half be 
length, greenish horn color. It has been found in Ohio, 
Indiana, Illinois, Michigan, Tennessee and Alabama. Fig. 
82 shows the shell with the animal extended. The creeping 
disk is bent upon itself. The opereulum may be seen on 
the hinder portion of the body, and the tentacles and eyes 
are seen near the aperture of the shell. 
 -Melantho. decisa Say, Plate 9, fig. 11, represents the spe- 
cies common to the New England States. Some specimens 
. are very smooth and bright green in color. They are all 
. devoid of an apex, and this is a characteristic feature. 
___ Sometimes the shell is found reversed; that is, the spire 




