Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: This closeup shows the tegmen to advantage

Photo title: Another view of the same Crinoid

Taxa present: Dolatocrinus liratus

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: Collected in 1994, Ken had many years to enjoy this wonderful example of Megistocrinus before he died a few years ago. We collected this at Partridge Point in Alpena and the crinoid was completely covered with bryozoans that can still be seen covering the plate. Ken, at the time, was not optimistic about how this would turn out and until it was cleaned by Scott Vergiels, he did not know what a treasure he had.

Photo title: This magnificent complete crinoid was the pride of Ken Dobson's collection

Taxa present: Megistocrinus nodosus

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: This example of a complete Dolatocrinus shows all the parts in the round. Two arms are missing but this allows the tegmen to be seen.

Photo title: A beautiful complete crinoid in matrix with stem and arms.

Taxa present: Dolatocrinus liratus

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Milan, Washtenaw, MI

Strat unit: Silica formation

Submitter notes: This image is of a large plate from the head of a Devonian Fish. The Nuchal plate was at the very back of the top of the head and the notch at the top of the photo would have been the back towards the tail area. U.S. ten cent piece for scale.

Photo title: Large, Nearly Complete, Nuchal plate from Devonian Arthrodire Fish

Taxa present: Protitanicthys rockportensis

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Sylvania, Lucas, OH

Strat unit: Silica formation

Submitter notes: This plate shows the extensive 'armor' of these early fish

Photo title: Another Arthrodire fish plate from the Ken Dobson collection

Taxa present: Protitanichthys rockportensis

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Sylvania, Lucas, OH

Strat unit: Silica formation

Submitter notes: These three Paraspirifer bownockeri brachiopods show Hederella bryozoa on the bottom fossil and Cornulites worm scars, and the holes made by Clionoides, a boring sponge on the upper left example. From the Ken Dobson Collection.

Photo title: A Lovely cluster of Large Silica Brachiopods in matrix with epifauna.

Taxa present: Paraspirifer bownockeri, Hederella , Cornulites , Clionoides

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Sylvania, Lucas, OH

Strat unit: Silica formation

Submitter notes:

Photo title: A different view of brachiopod plate.

Taxa present: Paraspirifer bownockeri

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Submitted on 2014-10-08 by Ken Dobson

Location (approximate): Arkona, Lambton, ON

Strat unit: Arkona formation

Submitter notes: This collection of small pyritized fossils includes a brachiopod, a crinoid calyx, and two cephalopods, one straight and the other coiled. All but the brachiopod are from Arkona, Ontario. The Brach is from Milan, Michigan.

Photo title: A collection of small pyritized fossils from the Ken Dobson collection

Taxa present: Tornoceras , unidentified cephalopod , Arthroacantha carpentari, Rhipidomella penelope

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: This large Placoblastus blastoid is in matrix and slightly crushed.

Photo title: Large Devonian blastoid from Alpena, MI

Taxa present: Placoblastus obovatus

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: This shows two additional blastoids free of matrix but weathered somewhat.

Photo title: Two additional blastoids from Alpena, MI

Taxa present: Placoblastus obovatus

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Sylvania, Lucas, OH

Strat unit: Silica formation

Submitter notes: The muddy bottom of the Devonian seas over Michigan seemed to have few hard places for animals to attach and therefore almost any hard surface was prime real estate. This inarticulate has attached itself to the larger brachiopod for a safe place but this proved a mistake as they died togather. Some small bryozoan also have grown on both.

Photo title: A Large Brachiopod with a small inarticulate Brachiopod attached.

Taxa present: Orthospirifer cooperi, Petrocrania hamiltonae, Hederella

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Milan, Washtenaw, MI

Strat unit: Silica formation

Submitter notes: This seems to be just a random association between this Platyceras snail and the large brachiopod, Orthospirifer. These are always suspect as the snails are noted to bore into brachiopods to eat their contents as they also did with crinoids.

Photo title: random association of snail and brachiopod

Taxa present: Orthospirifer cooperi, Platyceras bucculentum

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Arkona, Lambton, ON

Strat unit: Hungry Hollow formation

Submitter notes: These Bactrities are common in the Arkona shale but rarely are they this complete due to the extremely soft shale. This is very delicate and a few more rain drops would have destroyed this association.

Photo title: Small pyritized cephalopod from Arkona, Ontario from the Ken Dobson collection

Taxa present: Bactrites arkonensis

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Arkona, Lambton, ON

Strat unit: Hungry Hollow formation

Submitter notes:

Photo title: A closer view of Bactrities

Taxa present: Bactrites arkonensis

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Arkona, Lambton, ON

Strat unit: Arkona formation

Submitter notes: This small plate shows two species of crinoid from one location.

Photo title: A plate with two different species of crinoid from Arkona, Ontario

Taxa present: Corocrinus calypso, Decorocrinus arkonensis

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Arkona, Lambton, ON

Strat unit: Arkona formation

Submitter notes:

Photo title: A closer view of Corocrinus

Taxa present: Corocrinus calypso

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Arkona, Lambton, ON

Strat unit: Arkona formation

Submitter notes: Although this is not a complete crinoid crown, enough of the caalyx and anal tube or sac can identify the species.

Photo title: A closer view of Decorocrinus

Taxa present: Decorocrinus arkonensis

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Arkona, Lambton, ON

Strat unit: Arkona formation

Submitter notes: Here is a different specimen from Ken's collection that show the complete crown, arms, stem and anal sac extended.

Photo title: A complete crown with stem and anal sac

Taxa present: Decorocrinus arkonensis

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Submitted on 2008-10-07 by Ken Dobson

Location (approximate): Arkona, Lambton, ON

Strat unit: Arkona formation

Submitter notes: This shows the anal sac or tube.

Photo title: Another view of the same Crinoid

Taxa present: Decorocrinus arkonensis

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Submitted on 2008-10-06 by Ken Dobson

Location (approximate): Milan, Washtenaw, MI

Strat unit: Silica formation

Submitter notes: This shows more detail of the nice Phacops/Eldredgops from Milan in Ken's collection

Photo title: A Closeup view of the Trilobite in previous photo

Taxa present: Phacops rana crassituberculata

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