Late Cretaceous gastropods belonging to genus Lysis Gabb, 1864, from the Pacific slope of North America, bridge the morphologic gap between turbiniform trichotropids and limpet-like calyptraeids. Development of the depressed and broadened inner lip/co . . .

Two new genera and ten new species of shallow-marine, warm-water gastropods are reported from several Upper Cretaceous formations found between British Columbia and southern California. The buccinid Zaglenum new genus is represented by two new species . . .

Rare specimens of three new species of the Late Cretaceous buccinid gastropod Deussenia Stephenson, 1941, are reported from California. Deussenia sierrana sp. nov. is from lower Campanian strata in the Chico Formation in the Pentz area, Butte County, . . .

Opines constitute a small subfamily of Mesozoic astartid bivalves that lived mostly in the Tethys Sea region. They first appeared in western Europe during the Middle Triassic, became most widespread during the Jurassic and had their first undoubted ap . . .

Specimens of the large, shallow-marine, volutid gastropod Volutoderma Gabb, 1877, herein recognized only from strata of Late Cretaceous (Coniacian through early Maastrichtian) age in British Columbia, Washington, California, and Baja California have c . . .

The Cretaceous and early Cenozoic species of the shallow-marine, warm-water bivalve Plicatula from California (United States) and Baja California (Mexico) are reviewed, and three new species are named. All of these species are representatives of Plica . . .

Three new species of the shallow-marine, warm-water bivalve Plicatula are reported from the upper Paleocene Santa Susana Formation of southern California. Plicatula simiensis new species is from the middle part of the formation on the south side of Si . . .

The shallow-marine gastropod Potamides tenuis Gabb, 1864, from Upper Cretaceous (Campanian Stage) rocks in northern California, western Washington, and southwestern Canada, belongs to the gastropod genus Boggsia Olsson, 1929, formerly known only as tw . . .

Two new genera and three new species of extinct buccinoid gastropods are described and named from the Pacific slope of North America. The buccinid? Ornopsis? dysis new species is from uppermost Maastrichtian (uppermost Cretaceous) strata in the Dip Cr . . .

Ten new species of neritid gastropods are described from the fossil record of the Pacific slope of North America. Nerita (Amphinerita) eos sp. nov., from northern California, is of Early Cretaceous (Hauterivian) age and is the earliest record of Amphi . . .