Sl. Olson, A GIANT PRESBYORNIS (AVES, ANSERIFORMES) AND OTHER BIRDS FROM THE PALEOCENE AQUIA FORMATION OF MARYLAND AND VIRGINIA, Proceedings of the Biological Society of Washington, 107(3), 1994, pp. 429-435
Presbyornis isoni, new species, is described from a humerus and an ala
r phalanx from marine sediments of the late Paleocene Aquia Formation
in Maryland. About the size of the smallest living species of crane (G
ruidae), it was much larger than any previously known member of the Pr
esbyornithidae. Other fragmentary bird remains from the Aquia Fromatio
n are noted, several of which may be referable to the suborder Phaetho
ntes of the Pelecaniformes. Additional Paleocene birds from eastern No
rth America occur in the Hornerstown Formation of New Jersey, which is
now considered to be Danian (early Paleocene) in age, rather than lat
e Cretaceous.