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Stop The Press !!!!

PostPosted: Dec 20, 2007 1:38 pm
by Larry E. Matthews
I see you were talking about the NEW photograph.

No problem: Cystoid

I've got some in my collection that look exactly like that. Look carefully and you can see the plate structure.

In layman's terms, cystoids are sort of like primitive crinoids.

Larry E. Matthews
NSS #6792-F

PostPosted: Dec 20, 2007 2:04 pm
by gillip
The "soccer ball" is definately an echinoderm, but probably not a blastoid. A blastoid would have 5 ambulacra, which are groves lined with brachioles (long, thin arms) which carried food up the ambulacra to the mouth located at the top of the theca (body). I would have to agree with Larry that it is a cystoid echinoderm.

Re: Any ideas what this is?

PostPosted: Dec 27, 2007 9:00 am
by Squirrel Girl
Dangerjudy wrote:Any ideas what this is? Is it a fossil? I think the Pell City guys dubbed it, "The Phlopenator". :-) Check out the pics before and after it for more views.

edit - I can't get the link to work as clickable. Here's a pic:


OK, I just got this answer back from another paleontologist friend of mine:

The fossil has me stumped. My best guess is echinoderm. The reason I say that is that it appears to be a fairly evenly colored whitish fossil not unlike some crinoid crowns I've seen. It also appears that the left side is fractured or abraded and that the spines are hollow. There is a crinoid in the Silurian, Crotalocrinus if memory serves (although it often doesn't) that had spiny projections at the base of the crown but usually all I ever saw were internal molds so I'm not sure how closely they compare with the cave fossil. There do appear to be faint parallel lines running diagonally across the fossil that might represent cleavage planes typical of echinoderm calcite, but the two fractures at ~ 90 degrees argue against that idea. I agree that there is a bilateral symmetry to the fossil but I have also heard of echinoderm symmetry being described as biradial. Anyway, I'm sticking with echinoderm and quite possibly crinoid.