Onivalves. 33 
shell; it is also furnished with what we commonly 
call horns, naturalists say tentacles, from the Latin 
tento—trying, or essaying; with these the creature, 
as it were, feels its way, being extremely sensitive; 
they answer the purpose of organs both of sight 
and touch; put your finger slowly towards one of 
them, and you will observe that, even before con- 
tact, it begins to retract, or draw in, as though 
sensible of the approach of some opposing body, as 
it no doubt is. These horns of the Snail, then, are 
its feelers—eyes to the blind, fingers to the finger 
less ; so God provides for his creatures all that may 
be necessary for their existence, and compensates 
for the deprivation of one sense or organ, by some 
admirable contrivance which meets the necessities 
of the case.* 
* It appears likely that the little knobs at the end of 
the Snail’s feelers, are, as some naturalists assert, in reality 
eyes; if so, we were wrong in calling the creature blind. 
Yet is their position and construction so different from 
organs of sight generally, that they serve rather to 
strengthen than invalidate the above observations. The 
number of the horns varies in different kinds of snails from 
two to six,and some have none at all. These tentacles, 
when present, are always situated above the mouth; some 
of them have the knobs at the base, others at the sides; 
and it has been conjectured that they may be organs of 
smell, as well as of sight and touch. 
