
MOLLUSCS, VERMES AND HYDROZOA 

Eastern and Middle States and there is but one in the Southern States, 
L. pilsbryi of the Chipola River, Florida, a very rare species. 
VatvaTA. These small snails never exceed 14 to 3, inch in diameter 
and are principally prized on account of their odd appearance and the 
curious formation of their water-breathing organs or branchia. Most of 
the species are almost exclusively vegetable feeding and destructive to 
plants, and but few should be introduced into the aquarium, though they 
are comparatively harmless, due to their small size. 
V. tricarinata. Fig. 149, hasaslightly depressed turbinate, translucent 
yellowish-and greenish-brown shell 14 inch in diameter, of three to four 
smooth whorls with faint 
lines of growth and _flat- 
tened spire. The body 
is slightly translucent, the 
plume-like branchial fila- FIG. 149. Valvata tricarinata, Enlarged. 
ments long, the eyes black, the posterior of the foot extending nearly to the 
circumference of the shell, and the thin operculum near the extremity of 
= the foot. It is ovi- 
parousand vegetable 
Saban feeding and inhabits 
FIG. 150. Valvata bicarinata. Enlarged. the Eastern and 
Middle States generally, with a kindred slightly larger variety, /. bicarinata, 
Fig. 150, native in the Schuylkill river and its tributaries. It is about 
3ginch in diameter. 
V. sincera, Fig. 151, has a globose-discoidal faintly striated brownish- 
green shell, consisting of three and a half accurately rounded whorls which 
enlarge rapidly from the apex. ‘he suture is deeply impressed, the spire 
flattened and the apex 
obtuse. This snail is 


seldom over j; to 4 

inch in diameter and 
occurs in Vermont and FIG. 151. Valvata sincera. Enlarged. 
the Northwestern States. There are other species of the Valvata but they 
do not occur in the Eastern or Middle States. 
Amputtaria. This family has no members inhabiting waters of the 
Eastern and Middle States. All the species are large and handsome; but 
as their size would lead to the inference that they would be destructive to 
aquarium plants, experiment would be advisable before introducing them, 
as their food is vegetable and those kept in confinement eagerly devour 
lettuce. They are nocturnal in habits and seldom appear out of the shell 
during the day. They are interesting inmates for the Terra-aquarium. 
225 
