[Simulated (OP)]

What are they? Why don't some of my fingers have them? lol thanks

[elegantlywasted]

Are you talking cuticle (the skin around the nail)? Or are you thinking of the moon (half moon shaped line at the bottom of your nail)?

[Simulated (OP)]

The moon looking thing.

[Karen W.]

Like Meg said, it is the moon!

[Simulated (OP)]

Why's it there?

[Bored chemist]

http://en.wikipedia.org/wiki/Lunula_(anatomy)

[Simulated (OP)]

Ah thanks

[chris]

Sorry that I'm arriving at this question a bit late - I only just saw it!

As referred to above, the pal half-moon shaped structure at the base of each of your fingernails, and most pronounced on the thumb, is the lanula.

LANULA.jpg (245.5 kB . 579x709 - viewed 3657 times)

This structure corresponds to part of the growth plate for the nail. That means it is the location of the stem cells that produce the nail material, which comprises bundles of keratin laid down in the lanula. The shape of the lanula corresponds to the shape of the developing nail, so if the lanula is damaged then the resulting nail will also be deformed.

So if you bite your nails, stop before you get to that point. Or, better still, try not to bite your nails at all!