Fish Monger
The fish here made me sad - the presentation doesn't give you the sense that this person really cares about the fish. We aren't anywhere near the ocean so I suspect much of this is freshwater fish.
Ascidians - Halocynthia roretzi
The internet has come through - apparently they are ascidians - specifically Halocynthia roretzi. Ascidians are sea squirts — hermaphrodite marine invertebrates that live in shallow ocean waters, and which are thought to exhibit characteristics of the evolutionary ancestors of chordates and vertebrates.
(Thanks goes to Karen Sanamyan at ascidiacea.com/