Asaphus kowalewskii

Fantastic trilobite. The antenna are amazing (at least, I assume that's what they are). What does this specimen look like head on?

Those aren't antennae, they're eye stalks. I've wanted this species for a while because they're so unusual. The theories is that they lived on a turbulent sea bottom and this would allow them to see above the sediment or that they buried themselves in the sediment for protection, with just the eyes exposed.