Fossil taxa described in 1900

species of bird (extinct)

Trigonias (Greek: "triangular" (trigonos), "ias" [denotes possession]) is an extinct genus of rhinocerotid from the late Eocene (Chadronian) some 35 million years ago of North America.

species of mammal (fossil)

Gallinuloides is a prehistoric genus of pangalliform bird. It lived about 48 million years ago in North America. The type specimen was found in a Green River Formation deposit in Wyoming.

Diplomoceras is a genus of ammonites included in the family Diplomoceratidae. Fossils of species within this genus have been found in the Late Cretaceous sediments (age range: Campanian-Maastrichtian). D. maximum had coiled shell length about , uncoiled shell being to over , with body chamber around . Some partial specimens may belong to shell with length around . Studies of Diplomoceras suggest that members of this genus could reach lifespans of over 200 years.

genus of mammal (fossil)

Acrioceras is an extinct genus of cephalopods belonging to the ammonite subclass.