Glossary
Here I will explain some words relating to snails you may not understand:
Aestivating - when snails hibernate, forming a thin epiphragm over their aperture and staying there for up to a few months, snails do this in very hot summers.
Aperture - the hole at the base of the shell for the snail's body to come through.
Apex - the tip of the shell.
Body whorl - the largest whorl of the shell, the whorl ending at the mouth.
Columella - The internal column around which the whorls revolve, the verticalaxis.
Conical - used to describe a long thin shell.
Contracting - when the body is brought inward by the snail.
Dextral - shell coiling clockwise.
Discoidal - used to describe a shell which is circular and flat.
Epiphragm - a membrane of dried slime over the aperture when the snail aestivates.
Hibernation - When the snail goes to sleep during the winter.
Hypostracum - the inmost layer of the snails shell.
Love dart - a tiny translucent dart which the snail inserts into another snail before mating. It stops digestion of the sperm, so more sperm is fertilised.
Lip - the thickened edge of the shell around the aperture.
Mantle - the area of flesh underneath the aperture, from where the foot protrudes.
Operculum - snails of the subclass prosobranchia have a door to the aperture which is on their tail. this closes the aperture and avoids moisture loss.
Ostracum - the second layer to the snails shell. The main layer of the snail's shell.
Periostracum - the outermost layer to the shell, which contains pigmentation.
Pneumostome - the breathing hole, located on the mantle.
Radial - used to describe stripes or striae that go towards the apex of the shell, as opposed to spiral.
Radula - organ the snail uses to scrape food and eat it. It is situated at the base of the head.
Retractable - something which can be brought inward e.g. the snails foot or the tentacles.
Sexual organs - organs which enable the snail to procreate.
Sinistral - shell coiling anticlockwise.
Spiral - used to describe stripes or striae that follow the whorls.
Spire - all of the shell above the body whorl.
Sutures - the junctions between successive whorls.
Terrestrial - a land animal.
(Apertural) Tooth, Teeth - shelly prominences in or near the aperture of the shell.
Umbilicus - A hole or depression the whorls coil around. Usually seen in snails with flat shells.
Visceral hump - the flesh inside the snails shell, which contains most of the organs.
Whorl - any complete 360 degree coil of the shell.
