Black grains close to skin

Question
I have a long haired cat that never goes out.  Recently I've felt and seen small black grains when I pet and brush her.  They seem to be only on her back towards her tail.

My initial reaction would be fleas, but I have not been able to see any, and it seems unlikely since it is May and the winters are very cold here.

Do you have any ideas?

Thanks

Answer
thats called flea dirt.flea dirt consists of flea poop and flea eggs. if its near her tail that means you cant see any fleas because they are living and hiding inside her..going up under her tail and in. you will need to treat her for fleas soon before she becomes infested. even if its not fleas, which i really think it is, treating her for fleas wont hurt her. also you might want to buy a flea comb and comb her daily to get the flea dirt off of her. this will remove a lot of the eggs, thus cutting down on the number of fleas growing on her.