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.
Limpets, mussels and barnacles on a rock in the intertidal zone. Gastropods, or univalves, are the largest and most successful class of molluscs. 60,000â75,000 known living species belong to it. Most of are marine, but many live in freshwater or on land. Their fossil record goes back to the later Cambrian. Slugs and snails, abalones, limpets, cowries, conches, top shells, whelks, and sea slugs are all gastropods. The gastropods are in origin sea-floor predators, though they did evolve into many other habitats. Many lines living today evolved in the ...