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Leighla
 #1 
I found this in my backyard in KY, can anybody tell what it is?

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Mike Streeter
 #2 
Leighla,

Looks like a cephalopod fossil in fossiliferous limestone.  Cephalopod fossils are relatively common in Kentucky limestones.

Mike
Leighla
 #3 
thanks Mike!
Bob Harman
 #4 
This posting from last year has a fossil misidentification. I will reply now to correct the identification.

 The example is clearly a piece of fossiliferous limestone with a number of different invertebrate fossils. The largest example, in the center of the piece, is a segment of CRINOID STEM.  It is NOT a cephalopod. Crinoids were common in the Mississippian age and less common in other ages. Crinoid were animals, commonly known as SEA LILLYS, with many species described.   The heads of these animals waved in the sea currents feeding on the passing particles in the water.   The heads were supported on the stems, a segment of which is seen here. Some known stems are 10 - 15 feet in length.   A few species of crinoids or similar forms are still found today.   BOB
Mike Streeter
 #5 
Bob,

While I'm certainly not a paleontologist and therefore no expert on Kentucky fossils, I beg to differ with your identification.  Kentucky crinoids, by and large, do not demonstrate pronounced tapering as is generally the case with cephalopods and is shown by the predominate fossil shown in the picture.  While this is not to say that the fossil may indeed be an unusually tapered crinoid stem, my best guess from the picture is that it is more likely a cephalopod.

The following is a picture of a couple cephalopods from the Kentucky Geological Survey's web page:

[cephs_intro_a] 

According to the Kentucky Geological Survey, straight-shelled (orthocone) cephalopods are common in Ordovician limestones in the Bluegrass Region of Kentucky.  Some incomplete orthocone fossils have been found along the Kentucky River Palisades that were four feet long; the living animal was probably eight feet long.

While I'm not 100% certain whether the fossil is a cephalopod or a crinoid stem, I'd bet that Leighla would be OK with knowing that it is either or since it appears that she had no idea what type of fossil it is.

Mike
Al O
 #6 
I think Mike got this right from the beginning. This looks very much like the slightly tapered cones of what are called straight cephalopods. Not to attempt a very specific species ID here but check out photos of the genus Michelinoceras. Compare that to the generally straight columnals of crinoid stems.

Best Regards,
Al O


Al O
 #7 
OK Mike,

Beat me to it!

Best Regards,
Al O
Mike Streeter
 #8 
Al,

Always glad to see you're still out there attempting to keep me on the straight and narrow!

Mike
Bob Harman
 #9 
I will accept your identification as probably being correct. Not absolutely certain that it isn't a crinoid stem segment, but looking at the examples again, you all are probably right.      BOB
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