Probably leafminers.

thats some nice macro photography ... but could we see the whole plant ... and see if anything else is going on

ken

Of course! here is a pic of the whole plant. It seems healthy, but I thought I should take measures before it gets out of control. Thanks party_music50 for the potential identification... I looked it up and the pics on the net look very similar.... so that could well be it. I wonder if these bugs are going to enjoy eating my aloe after it has been marinaded in neem oil.

Oh, by the way, I was reading that the way to deal with leafminer is to cut off all the effected leaves (that would be all of them in this case) and squeeze the effected areas on new emerging leaves. Apparently squeezing the leaves crushes the larvae.... I am hoping that neem oil and detergent alone would be enough because the other method sounds like it was invented by someone who has something against plants.