boy or a girl

Question
how can u tell if your hermit crab is a boy or a girl?

Answer
Dear Tara,
thank you for your question.
To sex your crab, it needs to come out his shell a bit more than normal. When they try to climb the glass of the crabitat is a good moment to take a look. You can also hold the crab by the shell so that it has to strectch to reach the ground (not all crabs will do so, though). Never try to force the crab to leave the shell, they will hold on and let themselves sooner be pulled apart than leaving the shell.
If you can get the crab to hang out of the shell far enough, take a look at the last big pair of legs. Females have two openings there, on the last segment. Those are the gonopores, where the male inserts his spermatophore (what invertebrates have instead of a penis) during mating.
Here are good pictures of male and female crabs:
http://www.crabbagepatch.com/crabanatomy.html
I hope I was of some help to you
Jennifer