Fisherites Chlorophytes Fossil

These pictures show a fossil of calcareous green algae (chlorophytes) from the Ordovician Period. They are called Fisherites sp. of the order Dasyclads and family Receptaculites. The fossil was found in the Galena Formation of Minnesota.   Second picture shows a cross section of the fossil.
Thanks to Herb for the images.

Mississippian Age Cornulites Fossil

Cornulites worm tube fossil found in the Indian Springs Formation of Crawford County, Indiana. The worm tube is located in the picture to the upper left of the blastoid. Fossil is dated to the Mississippian Period. 

Thanks to Kenny for the picture.

Devonian Hindia Sponge Fossil

This sponge fossil appears to be a Devonian period Hindia sphaeroidalis. This fossil as found in the Nelson County, Kentucky and is from the Beechwood Limestone.

Thanks to Kenny for the picture.