Atlantic menhaden (Brevoortia tyrannus). I've posted before on how tasty these ubiquitous cuplieds seem to be to a dogfish, and it's not surprising that scales resembling menhaden scales show up with a lot of my unknowns. Menhaden have a fair amount of variation in the shape of their scales. Fortunately, I have a lot of menhaden scale samples.
Bay anchovy (Anchoa mitchilli). These fish show up in the hundreds, usually intact. Dogfish must just swim through large schools oft these would-be pizza toppings with their mouths open. So far the highest count in any one stomach has been 253 anchovies, and they weren't even the only things in the stomach. Anchovies must pack efficiently. I'll need to get a better picture of these scales, since I'm not sure these ones aren't multiple scales stuck together.
Atlantic croaker (Micropogonias undulatus). These scales could probably be lighted better, and I'm looking to get more samples of these, because they're a pretty nondescript scale. In contrast to the anchovies, there are typically only 1-3 small croaker in any given stomach, and they don't turn up that often. Strangely, most of the croaker I've found have been in the middle of big clumps of anchovies.