Help identify these new bumps

Indoor cat, so my first thought isn't fleas. (It could be -- sometimes a friend's dog is over -- but could it be anything else?) There are a whole series of these bumps around his neck.

Gosh, I always thought fleas ran around, not clumped up in certain spots, which those pictures look like.  But it certainly doesn't look like a tick either.  I have no idea what that is, yet you say his neck is ringed with them?  Are there several in each spot, like the picture looks like, or is this "thing" just a lumpy thing, like a scab?  What happens when you get it wet?  Does it appear to be living?  Sorry, I can't quite tell from the picture.

Does he scratch at them? 

We concluded that we were being alarmists and that he just scratched himself. Indoor cats do get sightly long nails, sometimes. 

My cat had a few of these same scab type things a few months ago. It appeared after I gave her a flea treatment as a preventative measure so I thought it was a reaction to that. I brought her to the vet where they did a skin-scraping test for mites; that came back negative. They ended up not finding a definite answer but they gave her an antibiotic shot which cleared it up.

My cats have given themselves sores like that from time to time. It's generally a reaction to flea's and being itchy so make sure her flea treatment is up to date. A couple of baths with some salt water should help them heal quickly and if they don't maybe get them checked