I have been using the permethrin spray for a while, but I think the mites have grown a resistance to the stuff. :hmm I can't always be where my chickens are to treat them, so the treatment hasn't been as thorough as I wanted it to be. Though I really thought I had got them this time, I guess not.
Honestly, I can't tell the difference between the two. @Justso that's exactly where the lice were.
Anyway, thanks everyone for helping identify them! :)