Carboniferous Crinoid Calyx

The bottom of this crinoid calyx displays an attractive five plate flower pattern.  This unidentified calyx is from the Upper Mississippian Period.  The fossil was found in Indian Springs Shale Member of the Big Clifty Formation of Crawford County, Indiana. Three specimens are shown in this posting and each fossil is about 1 cm in diameter. UPDATE (2020): These calyx cups might be Phanocrinus or Bicidiocrinus.

Thanks to Kenny for letting me image his fossils for this post.

On a small side note, this is my 900th post.  I will now slow down my publishing rate which has been for a while 7 posts a week.  My plan is now just publish on Sundays and Mondays which should get the blog to 1000 posts in 2011.  If a special occasion or fossil needs to be posted, I will publish outside of this schedule.  If I have any daily readers, thank you for your dedication to this fossil blog.

Looking for a daily read, check out the posts on the ever active Fossil Forum and good geology news and nifty info read the GeoBulletin.

Eucalyptocrinus Crinoid Calyx

The Eucalyptocrinus crassus (Hall, 1863) crinoid calyx with arm fragments and small stem section. Found in the Waldron Shale of Clark County, Indiana.  Found, imaged, and prepped by Kenny.  This Silurian period fossil is considered an index fossil for the Waldron Shale. 

The Waldron Shale fossils were documented in the Indiana Department of Geology and Natural History Eleventh Annual Report with John Collett State Geologist, 1881 published by Wm. B. Burford, State Printer of Indianapolis, 1882.  Below are some of the illustrations shown in this report.

Eucalyptocrinus crassus - Plate 17 Figure 5

Eucalyptocrinus crassus - Plate 17 Figure7

Eucalyptocrinus crassus - Plate 18 Figure 4

Eucalyptocrinus crassus - Plate 18 Figure 5

Eucalyptocrinus crassus - Plate 18 Figure 6

Eucalyptocrinus crassus - Plate 18 Figure 7

Glyptocrinus Crinoid Calyx

This calyx fossil was found in the Waldron Shale of Clark County, Indiana.  It is somewhat worn but appears to be some sort of Glyptocrinus sp.  This crinoid existed in the Silurian Period. The white spots on the images are caused by light reflecting off pyrite crystals.

This last three illustrations Plate 13, figures 8-10 in the Indiana Department of Geology and Natural History (Eleventh Annual Report) from 1881.