Micropaleontology

Marine microfossils: (diatom, ostracod, radiolarian, sponge spicule, radiolarian, planktonic foraminiferan (two), coccolith)

Micropaleontology (American spelling; spelled micropalaeontology in European usage) is the branch of paleontology (palaeontology) that studies microfossils, or fossils that require the use of a microscope to see the organism, its morphology and its characteristic details.