A1 Saturday and Sunday, or Friday evening until Sunday night; the part of the week in which many people living in the West do not go to work: This/Next weekend we're going to see some friends. I have a lot of homework to do over the weekend. He spent the weekend fishing with his brother.
clams, mussels, oysters, and scallops (class Bivalvia) 1  ark shell (family Arcidae) 2  cockles (family Cardiidae) 3  coquina clam (genus Donax) 4  gaper clams (Tresus nuttallii and Tresus capax) 5  geoduck (Panopea generosa) 6  jingle shells (family Anomiidae) 7  mussels (families Mytilidae and Unionidae) zebra mussel (genus Dreissena) 8  genus Nuculana.
Gastropods are the most diverse family of mollusks, including over 60,000 species of snails and slugs that live in marine, freshwater, and terrestrial habitats. Cephalopods, the most advanced mollusks, include octopuses, squids, cuttlefish and nautiluses. Most of the members of this group either lack shells, or have small internal shells.