Kehbe Posted April 10, 2012 Share Posted April 10, 2012 I am thinking this is a cephalopod. Found in the Pennsylvanian winterset limestone, Kansas City, Jackson county, Missouri. The dark spot on top appears to be the siphuncle. The only cephalopod I could find while surfing the internet that looks anything like this is a dawsonoceras cephalopod but I can't find a description of dawsonoceras from the Pennsylvanian, only from the Silurian. Is there any other ceph that would fit the bill? Thanks for looking and thanks in advance for any suggestions on the ID! pic1 pic2 pic3 pic4 pic5 pic6 pic7 pic8 It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change. Charles Darwin Link to comment Share on other sites More sharing options...
mikeymig Posted April 10, 2012 Share Posted April 10, 2012 I have found similar looking "things" in the Devonian shales of NY. I pick them up sometimes thinking they must be a fossil cephalopod but there not. I think they are some type of deformed nodule. mikey Many times I've wondered how much there is to know. led zeppelin Link to comment Share on other sites More sharing options...
fishguy Posted April 10, 2012 Share Posted April 10, 2012 Could it be a borrow? Link to comment Share on other sites More sharing options...
Auspex Posted April 10, 2012 Share Posted April 10, 2012 Could it be a borrow? That sure could have been the genesis, but there are layers to it, somewhat concentric (in an eccentric way), which makes me think there was some diagenetic chemistry at work too. "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
JimB88 Posted April 10, 2012 Share Posted April 10, 2012 I think we can eliminate Bison.. ( some had to say it since Tracer seems to be awol) seriously, the layers on it look sorta like the decorations on a Gastropod.... Link to comment Share on other sites More sharing options...
Missourian Posted April 10, 2012 Share Posted April 10, 2012 It looks like one of the chert nodules that often show up in the Winterset. It could be a diagenetically altered burrow fill. The evenly spaced grooves on the side may reflect thin bedding of the sediment. Context is critical. Link to comment Share on other sites More sharing options...
Herb Posted April 13, 2012 Share Posted April 13, 2012 I too believe it is a burrow of some kind "Absence of evidence is not evidence of absence"_ Carl Sagen No trees were killed in this posting......however, many innocent electrons were diverted from where they originally intended to go. " I think, therefore I collect fossils." _ Me "When you have eliminated the impossible, whatever remains, however improbable, must be the truth."__S. Holmes "can't we all just get along?" Jack Nicholson from Mars Attacks Link to comment Share on other sites More sharing options...
thanatocoenosis Posted April 13, 2012 Share Posted April 13, 2012 Huh, it is a big ol' snail... at least with the torsion to the test, that is what I see. 2012 NCAA Collegiate Round Ball Champs; and in '98, '96, '78, 58, '51, '49, and '48, too. Link to comment Share on other sites More sharing options...
Auspex Posted April 13, 2012 Share Posted April 13, 2012 I don't think it actually spirals... "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
Missourian Posted April 13, 2012 Share Posted April 13, 2012 For comparison, here's an 'uncooked' burrow fill in the upper Winterset beds: Note the large concretion in the upper left. It may have been on its way of calcifying the silt and fine sand laminae surrounding the burrow, but the diagenetic process was stopped. Your specimen, if a burrow, is completely cemented, and was subjected to further silicification. Context is critical. Link to comment Share on other sites More sharing options...
BobWill Posted April 13, 2012 Share Posted April 13, 2012 (edited) I don't think it actually spirals... Auspex is right. The way to tell is to compare pictures 1 & 3. In 1 with the pointy end down the sections slant upward left to right the way you would expect a snail to do. In pic 3 with the pointy end up and the other side showing, the visable section slants downward left to right, opposite of a snail. Try this holding a snail you can turn over to see the effect. If these are roundish discs, maybe they started out not slanted at all and experienced distortion over time. Edited April 13, 2012 by BobWill Link to comment Share on other sites More sharing options...
howard_l Posted April 14, 2012 Share Posted April 14, 2012 That one I am not so sure about, It looks more Gastropodish from the pictures. Does it have any evidence of septa or a siphuncle on the end. Howard_L http://triloman.wix.com/kentucky-fossils Link to comment Share on other sites More sharing options...
thanatocoenosis Posted April 14, 2012 Share Posted April 14, 2012 (edited) Auspex is right. The way to tell is to compare pictures 1 & 3. In 1 with the pointy end down the sections slant upward left to right the way you would expect a snail to do. In pic 3 with the pointy end up and the other side showing, the visable section slants downward left to right, opposite of a snail. Try this holding a snail you can turn over to see the effect. If these are roundish discs, maybe they started out not slanted at all and experienced distortion over time. I see about 20° slant on the spire- front and back- in the same direction. Too, as these are from Jackson Co. Missouri, I don't think that area has experienced any tectonics that would distort primary features. Edited April 14, 2012 by thanatocoenosis 2012 NCAA Collegiate Round Ball Champs; and in '98, '96, '78, 58, '51, '49, and '48, too. Link to comment Share on other sites More sharing options...
BobWill Posted April 14, 2012 Share Posted April 14, 2012 I see about 20° slant on the spire- front and back- in the same direction. Too, as these are from Jackson Co. Missouri, I don't think that area has experienced any tectonics that would distort primary features. The slant is in opposite directions when you turn it upside down (up to the right pic 1 & down in 2). If it were a spiral it would slant the same way however you turn it. Try this with a gastropod to see the effect. Link to comment Share on other sites More sharing options...
thanatocoenosis Posted April 14, 2012 Share Posted April 14, 2012 (edited) If it were a spiral it would slant the same way however you turn it. Try this with a gastropod to see the effect. Doh! I totally missed that. It does slant the same way. It is a snail. Edited April 17, 2012 by thanatocoenosis 2012 NCAA Collegiate Round Ball Champs; and in '98, '96, '78, 58, '51, '49, and '48, too. Link to comment Share on other sites More sharing options...
Missourian Posted April 14, 2012 Share Posted April 14, 2012 My guess: Context is critical. Link to comment Share on other sites More sharing options...
thanatocoenosis Posted April 17, 2012 Share Posted April 17, 2012 The slant is in opposite directions when you turn it upside down (up to the right pic 1 & down in 2). If it were a spiral it would slant the same way however you turn it. Try this with a gastropod to see the effect. It does slant the same way(see my annotated photographs). It is a gastropod. 2012 NCAA Collegiate Round Ball Champs; and in '98, '96, '78, 58, '51, '49, and '48, too. Link to comment Share on other sites More sharing options...
BobWill Posted April 17, 2012 Share Posted April 17, 2012 It does slant the same way(see my annotated photographs). It is a gastropod. I see the white lines slanting upward to the right in the first pic and downward in the second. Does anyone else see spirals instead of slanted discs? I'm liking Missourian's explaination but must admit this is a new one for me Link to comment Share on other sites More sharing options...
Kehbe Posted April 18, 2012 Author Share Posted April 18, 2012 Okay, I had left this piece at work and every time I thought about checking it, I was at home or busy with something! I have studied it and have concluded in my infinite wisdom, uhmmhmm, actually just from observation, that it is more like discs stacked on top of each other and set on an angle rather than a spiral. If you put your finger on top of the ridge or on the edge of the disc and follow it around 360 degrees, you end up back where you started, on the same disc, not the one above or below it. In other words, it does not spiral. I tried to figure it out by looking at the pictures and it is deceiving. As much as I wish it were a 'big ol' snail', I believe it resembles Missourian's illustration more closely! Thanks all for the comments and the interest If I ever find out any different, I shall post my results! Here is a picture of both sides, side by side! It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change. Charles Darwin Link to comment Share on other sites More sharing options...
thanatocoenosis Posted April 19, 2012 Share Posted April 19, 2012 (edited) I see the white lines slanting upward to the right in the first pic and downward in the second. Does anyone else see spirals instead of slanted discs? I'm liking Missourian's explaination but must admit this is a new one for me The photos are opposite sides of the same specimen, hence, when flipped over, the spire will be an enantiomer of the other side(if I can borrow a term from out chemist friends). Look at the top of the specimen in the photographs... that protusion, notice how it is a mirror image in the two photos? It is a snail. EDIT: Look at the two photos that I annotated(front and back)... flip the one on the right onto the left one... viola! Edited April 19, 2012 by thanatocoenosis 2012 NCAA Collegiate Round Ball Champs; and in '98, '96, '78, 58, '51, '49, and '48, too. Link to comment Share on other sites More sharing options...
BobWill Posted April 19, 2012 Share Posted April 19, 2012 The photos are opposite sides of the same specimen, hence, when flipped over, the spire will be an enantiomer of the other side(if I can borrow a term from out chemist friends). Look at the top of the specimen in the photographs... that protusion, notice how it is a mirror image in the two photos? It is a snail. EDIT: Look at the two photos that I annotated(front and back)... flip the one on the right onto the left one... viola! When you flip the one on the right onto the left one you undo what you did to observe the difference seen on opposite sides. Leaving the images side by side you can see the slant going in opposite directions when viewed from each side, something that would not occur with a spiral. Link to comment Share on other sites More sharing options...
Missourian Posted April 19, 2012 Share Posted April 19, 2012 (edited) I don't know why I didn't mention this before.... Some of the upper Winterset beds have very unusual lithology. In places, sediments were partially cemented before they were compressed by the weight of overlying strata. This caused distortion of the original bedding planes. Any existing features, such as burrows, would have been distorted as well. My attachment a few posts back shows this quite well: (yellow = bedding planes; pink = cemented sediment; green = burrow) It is possible that Kehbe's specimen was subjected to such a distortion of the sediments. Note the faint laminae that seem to reflect the pattern in the 'fossil': In other words, the apparent morphology could be due, in part, to these distortions. Edited April 19, 2012 by Missourian Context is critical. Link to comment Share on other sites More sharing options...
Bill Posted April 19, 2012 Share Posted April 19, 2012 EDIT: Look at the two photos that I annotated(front and back)... flip the one on the right onto the left one... viola! Nope!! Heres a front and back of a gastropod. When viewed from front, back, left or right, the spiral always goes the same way. In most, rising from left to right. KOF, Bill. Welcome to the forum, all new members www.ukfossils check it out. Link to comment Share on other sites More sharing options...
Herb Posted April 19, 2012 Share Posted April 19, 2012 Unless you have a gastropod that goes from right to left, even the same genus can have right or left handed specimens. There is an Ordovician cephalopod "Cameroceras sp." when only the siphuncle remains looks almost exactly like this picture. Check in "Fossils of Ohio." There maybe something similar in another species. "Dawsonoceras" is Silurian. I still think it's a burrow. Sometimes, Dr. Freud, a cigar is just a cigar. "Absence of evidence is not evidence of absence"_ Carl Sagen No trees were killed in this posting......however, many innocent electrons were diverted from where they originally intended to go. " I think, therefore I collect fossils." _ Me "When you have eliminated the impossible, whatever remains, however improbable, must be the truth."__S. Holmes "can't we all just get along?" Jack Nicholson from Mars Attacks Link to comment Share on other sites More sharing options...
Bill Posted April 19, 2012 Share Posted April 19, 2012 (edited) Actually I did say, " In most, rising from left to right." I have a few specimens of Neptunea contraria. The Pliocene 'left handed whelk' (Contrary spiral), which rise from right to left. When viewed from any side the rise is still right to left. Edited April 19, 2012 by Bill KOF, Bill. Welcome to the forum, all new members www.ukfossils check it out. Link to comment Share on other sites More sharing options...
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