Mealy Bugs

These are mealy bugs. They suck the nutrients out of the plant. You can spray the affected areas with commercial houseplant insecticide, or take a small spray bottle and fill it with half distilled water and half rubbing alcohol. Let it sit for a few minutes or so and then spray clean with just water. If the infestation is not too severe, use a q-tip dipped in denatured alcohol (available at your drug store) and rinse off with water after treatment (prolonged exposure to alcohol can damage the leaves). You will likely have to repeat this several times over a couple of weeks. Mealy bugs are common and cause little harm in small numbers, but increase rapidly in the right conditions. It is easier to take care of them when the numbers are small.