Aquatic Lite 
107 
quickness of the snail to discover a dead 
fish. ‘he sense of hearing is probably 
not acute. In the case of the land-snail, 
the eye is at the end of a tapering, tubu- 
lar organ, resembling the finger of a 
glove. This eye can be pulled in, much 
as in pulling off a glove, the tip might 
stick to the finger. 
As a rule, the pond snail has no oper- 
culum, or trap-door. They are com- 
monly plant and alge eaters. They will 
eat vegetable matter, either living or 
dead, and will eat flesh from necessity 
or from A practical joker 
recently cleaned a sardine from a can, 
and placed it in the writer’s “big tank.” 
In a very short time the sardine was alive 
with snails. They surrounded it until 
there was no room for the late comers. 
But we observed that they did not fight 
for places in the circle. Late comers 
waited patiently until there was an open- 
ing. 
choice. 
There was no sign of eagerness, or 
of the larger ones displacing the smaller. 
The snail’s tongue is described as file- 
like in structure. It is flat and ribbon- 
like. Across it run a series of bilaterally 
symmetrical teeth, arranged in patterns. 
These patterns vary as widely in differ- 
ent snails as colors and shapes vary in 
tropical fishes. Each class, order, genus, 
species, and even sometimes different 
species in the same genus, differ in this 
respect. These varying tongue-patterns 
are valuable to scientists in classifying 
specimens, where exact work is desired. 
Some snails are lung-breathers, while 
breathe by The  lung- 
breather comes to the surface for his air. 
He rises suddenly to the surface, extends 
a tube-like organ above the surface film 
with an audible sound, and collects a sup- 
ply of air, to be taken to the bottom and 
consumed at leisure. Operculates live 
on the bottom and breathe by gills. Those 
without an operculum are commonly air- 
others gills. 
breathers. 
Water is not always necessary for the 
snail. Land snails do not require it for 
their habitat. River and pond _ snails, 
when dry weather comes, and the pond 
or stream dries up, bury themselves from 
two to four inches in the bottom. Some 
have even been found 18 inches in the 
mud. 
Every now and again some aspirant 
for membership in the already crowded 
Ananias Club will record the fact that 
river and pond snails have been known 
to live for years in a tin box, or glued to 
a cardboard mount. But no conchologist 
would preserve a snail without first re- 
moving the body. River and pond snails 
will live for several days packed in wet 
moss. ‘They have even lived in such a 
condition for two months, according to 
some authorities. One scientist mentions 
45 days out of water as a remarkable in- 
cident. Some of the Lymnaeidae family 
have been known to live for some time 
without rising to the surface for air. 
And yet if one were to seal a snail in a 
bottle filled with water, he would soon 
die. 
It is interesting to collect shells of dead 
snails from the bottom of one’s aquaria, 
and clean them by gently brushing with 
a weak solution of oxalic acid and a 
toothbrush, being careful not to remove 
what epidermis remains. Or if one wishes 
to collect live snails, they may be quickly 
killed by plunging them in hot water. 
It’s cruel, yet scientific. Upon examining 
the snail’s shell one will observe more or 
less vertical, parallel striations on the 
shell, and rings on the operculum. ‘These 
are growth rings. The snail adds growth 
rings after the fashion of a tree. Every 
now and then we will notice a dark line, 
or even a section of the shell, showing a 
different color. Some writers have held 
the opinion that this difference in sculp- 
