A Snail's Mouth

from The Sound of a Wild Snail Eating:

My snail possessed around 2,640 teeth. . .the teeth point inward so as to give the snail a firm grasp on its food; with about 33 teeth per row and maybe 80 or so rows, they form a multi-toothed ribbon called a radula, which works much like a rasp. This explained my snail's nodding head as it grated away at a mushroom; it also explained the odd squareness of the holes I had discovered in my envelopes and lists [that the author left near the snail's flowerpot overnight]. As the front row of teeth gets worn down, a fresh new row is added at the back and the radula slowly moves forward, being completely replaced over the course of four to six weeks. Radulae are adapted to a particular snail's diet and can be an identifying characteristic of a species.