MONTANA

FERGUS COUNTY

1 M ABOVE THE MOUTH OF DOG CREEK

CLAGGETT FORMATION

CAMPANIAN STAGE

MIDDLE SENONIAN SUBEPOCH

UPPER GULF EPOCH

LATE CRETACEOUS

STEM: TETRAPODA GOODRICH, 1930

SUPERCLASS: AMNIOTA HAECKEL, 1866

CLASS: AVES LINNAEUS, 1758

AVEBREVICAUDA PAUL, 2001

SUBCLASS: ODONTORNITHES MARSH, 1873

INFRACLASS: ODONTOHOLCAE NOVA

MAGNORDER: HESPERORNITHES

ORDER: HESPERORNITHIFORMES FURBRINGER, 1888

Family: HESPERORNITHIDAE Marsh, 1872

Subfamily: HESPERORNITHINAE Marsh, 1872

Coniornis altus
= *Hespornis montana