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I am just starting to plant potatoes and have noticed I have lots of black millipede looking things with white tummies that curl up into a spiral.

I have been told by a number of people that they attack certain varieties of potatoes including Desiree

What are these little creatures and how do I get rid of them

Not the least bit millipedy, but do you mean these?
http://www.uri.edu/ce/factsheets/sheets/cutworms.html

Millipedes do curl up, but I've never seen a white tummied one. Are they hard bodied or squidgy?

Dunno its stumped me with white belly.