Diatoms from North America

See images from the:

		Quaternary
		Tertiary
		Cretaceous
		Jurassic
		Triassic
		Permian
		Carboniferous
		Devonian
		Silurian
		Ordovician
		Cambrian
		Precambrian

Actinoptychus heliopelta
From the Tertiary in Maryland
© 1995 UCMP

Sceptroneis caduceus
From the Tertiary in Maryland
© 1995 UCMP

Unknown diatom (cingulum)
From the Tertiary in California
© 1997 UCMP