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It could be echinoderm. What I think I'm
seeing is a damage portion of articulated crinoid stem or arm. Since the
view of the specimen on the left side is appears to be damaged down the middle,
the sections on the left may appear offset from those on the right. The
picture of the same specimen on the right is also worn down, showing a cross
section of the hole through the center of the stem.
Then again, maybe Leigh is correct?!
Cheers
Andrew R. C. Milner
City Paleontologist
St.
George Dinosaur Discovery Site at Johnson Farm
2180 East Riverside
Drive
St. George, Utah 84790
USA
"There is no branch of detective science which is
so important and so much
neglected as the art of tracing footsteps" -- Sir
Arthur Conan Doyle, 1891
----- Original Message -----
Sent: Tuesday, November 29, 2005 1:51
PM
Subject: Re: paleonet Ordovician mystery
fossil
Not echinoderm. Vaguely like a charophyte
oogonium, but too big, early, complex, and marine. The left photo shows
ridges apparently alternating on the two sides, suggesting interlocking when
together. I suggest a small brachiopod, perhaps Plectorthis
or even Zygospira, with the hinge line and one end eroded off.
The central structure in the right photo might then be a remnant of the hinge
line, and there's a hint of a central (here, top) fold-sulcus pair.
Worth comparison, anyway.
-Leigh
To all paleonetters,
Hi - I'm hoping
someone can identify a mystery fossil found by one of my undergraduate
students on a geology field trip this past spring.
Below is the
internet address of 2 photos of the fossil. The file posted here will
take several moments to open
up.
http://www.geology.cwu.edu/facstaff/glassa/Stuff/Fossil.ppt
The
pics aren't fantastic, but I think they're sufficient to show the
morphology.
I initially (& naively) thought it might be a broken
segment of a stelleroid (starfish or brittle star), but a starfish/brittle
star worker has told me definitely NOT!
The fossil is 5 mm x 3 mm in
size. It was found as float, derived from either the upper Waynesville
Formation or the lower Liberty Formation (Richmondian Stage, upper
Cincinnatian Series, upper Upper Ordovician). It was found at Caesar
Creek Lake's emergency spillway, northeastern Warren County, southwestern
Ohio, USA.
Any thoughts or suggestions? If so, please contact
me off-line at:
stjohn.2@osu.edu
If a reasonable ID comes along,
I'll post that info. to the entire list.
Thanks for your
time,
James St.
John
stjohn.2@osu.edu
_________________________________
James
St. John
Founders Hall 156A
1179 University Drive
Ohio State University at Newark
Newark, Ohio 43055 USA
__________________________________
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