6. Timerus delphinocephalus & Diacalymene sp.

Timerus delphinocephalus (left)  & Diacalymene sp. (right)

Lower Silurian
Rochester Shale Formation
Caleb's Quarry, Middleport,
New York, U.S.A

1.5 cm (left) / 1.2 cm (right)