Tuesday, September 21, 2010

Eucalyptocrinus elrodi Calyx

Bottom of an Eucalyptocrinus elrodi (Miller, 1891) crinoid calyx with a partial covering of pyrite crystals.  Found in the Waldron Shale of Clark County, Indiana.  This crinoid existed in the Middle Silurian Period.

See a prepared E. elrodi  found in St. Paul, Indiana at Crinus's fossil web site.

See more examples of this species at the Weeks Trilobite site.

This particular species is not quite as common as the Eucalyptocrinus crassus which is an index fossil for this formation.

See the Weeks Trilobite web site for more examples of the Eucalyptocrinites crassus.

Crinus fossil web site also has an E. crassus pictured found in Sellersburg, Indiana as well as a holdfast found in Waldron, Indiana.

This fossil was sandblasted -- thanks Kenny!

Monday, September 20, 2010

Glyptambon Trilobite


Trilobite cephalon found in the Waldron Shale.  Middle Silurian Period was the age this creature lived.   It appears to be a Glyptambon verrucosus? Fossil found in Clark County, Indiana.  Fossil is somewhat small with cephalon being approximately 1.75 cm wide.

See Weeks Trilobites web site for a truly stunning specimen of this species of trilobite!


Sunday, September 19, 2010

The Trilobite Spiral




The Smithsonian Museum of Natural History of Washington D.C. has an extensive collection of Ohio trilobites on display.  It consists of three spirals that show the grow sizes of three common trilobites: Isotelus (Ordovician), Flexicalymene (Ordovician), and Phacops (Devonian).  They appear to be from Ohio and presented in an enrolled state.