Changes in the morphology and orientation of crystals have been tracked across the nacreous layer in pterioid bivalves, by SEM and X-ray diffraction. Early crystals nucleated on the organic membrane usually covering the outer prismatic layer. They formed

Phylogenetic relationships within the subclass Pteriomorphia (Bivalvia) were examined using sequences of the mitochondrial cytochrome c oxidase subunit I gene. The resultant Minimum Evolution phylogenetic tree strongly supports the existing superfamily-level

Pteria brevialata characteristically attaches to Hicksonella princeps (Cnidaria: Gorgonoidea) at depths > 10 m in Hong Kong and the South China Sea. Attachment is by a stout byssus to the basal regions of the gorgonian colonies. The shell appears typical

Marine bivalves of the family Myalinidae are an important benthic constituent of the Perm-ian Reef Complex of West Texas and New Mexico. We describe and summarize the myalinids from Lower and Middle Permian reef and near-reef settings and infer living