They include oysters, crabs of great size, and a small mussel, found in enormous numbers.
Hannibal is the trade centre of a rich agricultural region, and has an important lumber trade, railway shops, and manufactories of lumber, shoes, stoves, flour, cigars, lime, Portland cement and pearl buttons (made from mussel shells); the value of the city's factory products increased from $2,698,720 in 1900 to $4,442,099 in 1905, or 64.6%.
The sea mussel (Mytilus edulis) belongs to the second order of the class Lamellibranchia, namely the Filibranchia, distinguished by the comparatively free condition of the gillfilaments, which, whilst adhering to one another to form gillplates, are yet not fused to one another by concrescence.
The pearl mussel was formerly used as bait in the Aberdeen cod fishery.
This was manufactured from the Mytilus californianus, a mussel which abounds there.