Submitted on 2008-11-23 by David Thompson

Location (approximate): Alpena, Alpena, MI

Strat unit: Alpena formation

Submitter notes:

Photo title: Bottom (stem) view of previous three crinoid calyxes

Taxa present: Dolatocrinus asterias

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Alpena, Alpena, MI

Strat unit: Alpena formation

Submitter notes:

Photo title: Closeup view of largest caylx in previous entry

Taxa present: Dolatocrinus asterias

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Milan, Washtenaw, MI

Strat unit: Silica formation

Submitter notes: Both of these crowns are very small but this little one is only 7 mm high.

Photo title: Closeup of the smallest crown from previous photo

Taxa present: Eutaxocrinus wideneri

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Milan, Washtenaw, MI

Strat unit: Silica formation

Submitter notes: The US 10 cent piece is for scale .

Photo title: Big and little crinoid crown example of the same species.

Taxa present: Eutaxocrinus wideneri

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: This calyx was preserved in soft shale mud so that all the details were protected.

Photo title: well preserved caylx (bottom or stem view)

Taxa present: Megistocrinus multidecoratus

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes:

Photo title: Top or tegmen view of crinoid

Taxa present: Megistocrinus multidecoratus

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Milan, Washtenaw, MI

Strat unit: Silica formation

Submitter notes: Although not common, these fossils are found in the Silica. This shows a crinoid stem that has coiled back upon itself around its attachment point. In this case the crinoid has attached to the inside of a Phacops trilobite head. The top of the crinoid stem and cirri attachments can be seen with four coils of the stem all around it

Photo title: A fossil oddity.

Taxa present: unknown crinoid stem

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Milan, Washtenaw, MI

Strat unit: Silica formation

Submitter notes: Given the fauna at this location, I would venture to call this a Arthroacantha stem but there is not sufficient data to do so.

Photo title: Another view of coiled stem.

Taxa present: unknown crinoid stem

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Milan, Washtenaw, MI

Strat unit: Silica formation

Submitter notes: This is a very common brachiopod in the Silica and Arkona locations but that is NOT why I have put it on this site. This is the ventral view and is quite uninteresting really, not even complete. The story is on the other side.

Photo title: A common Silica brachiopod

Taxa present: Mucrospirifer thedfordensis

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Sylvania, Lucas, OH

Strat unit: Silica formation

Submitter notes: Attached to the slightly larger Brachiopod is a very tiny passenger that is complete in every way. This illustrates Jonathon Swift's famous quote; 'A flea hath smaller that on him prey, and these have smaller still to bite 'em; and so proceed ad infinitum.' This is not a prey situation but rather if it is hard and sits still; grow on it! The baby brachiopod is 5.6 mm long to the host's 20. mm.

Photo title: A tiny hitchhiker!

Taxa present: Mucrospirifer thedfordensis

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Sylvania, Lucas, OH

Strat unit: Silica formation

Submitter notes:

Photo title: Another view of the baby Brachiopod

Taxa present: Mucrospirifer thedfordensis

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Sylvania, Lucas, OH

Strat unit: Silica formation

Submitter notes: This lovely, complete caylx was found in the bottom of a boot print on the spoil piles of Sylvania, Ohio where I was able to retrieve it! 'acantha' means 'prickly' in Latin and each of the pustules on this calyx had a tiny movable spine on it to repel predators. these are often preserved but not in this specimen.

Photo title: A complete caylx

Taxa present: Athroacantha carpenteri

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Sylvania, Lucas, OH

Strat unit: Silica formation

Submitter notes: This tegmen is without a gastropod and the anal tube is at 6:00 o'clock position

Photo title: Tegmen view of previous crinod caylx

Taxa present: Athroacantha carpenteri

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Milan, Washtenaw, MI

Strat unit: Silica formation

Submitter notes: This Arthroacantha is from Milan, MI and is heavily pyritized but the Platyceras is clearly in place on the tegmen.

Photo title: Caylx with a gastropod

Taxa present: Athroacantha carpenteri, Platyceras bucculentum

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Milan, Washtenaw, MI

Strat unit: Silica formation

Submitter notes:

Photo title: Another view of crinoid/gastropod combination

Taxa present: Athroacantha carpenteri, Platyceras bucculentum

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Sylvania, Lucas, OH

Strat unit: Silica formation

Submitter notes: Note the 'prickly' thorns at the nodes of the arms which along with the spines on the caylx made these rather hard to hold. Note the gold pyrite triangle in the front arms where there had been a platyceras attached but was broken off.

Photo title: A crinoid crown.

Taxa present: Athroacantha carpenteri

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Sylvania, Lucas, OH

Strat unit: Silica formation

Submitter notes:

Photo title: The back view of previous crinoid

Taxa present: Athroacantha carpenteri

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Sylvania, Lucas, OH

Strat unit: Silica formation

Submitter notes:

Photo title: Detailed view of arms

Taxa present: Athroacantha carpenteri

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Sylvania, Lucas, OH

Strat unit: Silica formation

Submitter notes: The crinoid/snail combination is quite common and this is stem view of caylx

Photo title: A different species with gastropod

Taxa present: Gilbertsocrinus ohioensis, Platyceras bucculentum

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Submitted on 2008-11-23 by David Thompson

Location (approximate): Sylvania, Lucas, OH

Strat unit: Silica formation

Submitter notes: Note that in this speciman, there are multiple 'worm tubes' or Cornulites around the opening of the Platyceras. I have not seen this association before. Usually the Cornulites infest the lip of the large Paraspirifer bownockeri from the Silica and need an open area at their mouth. How they could have had this with the Platyceras tightly attached to the crinoid tegmen is not clear to me.

Photo title: Tegmen view of previous crinod caylx showing the snail (Platyceras) in position

Taxa present: Platyceras bucculentum, Gilbertsocrinus ohioensis, Cornulites

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