Wednesday, September 27, 2017

Just more backbones - as if we don't have enough of them!

Just a quick note to tell all you folks about more backbones that I've prepared. Sometimes the backbones cluster together - must be something about how the water currents & waves sorted items of similar density and shape together. Anyway, I have been working an a small rock about the size of two fists together. This rock has at least 6 backbones, maybe more. We have both centrums and centrums combined with neural arches. Some are rather unusual in the way the rib attachment knobs on the centrums look. I believe that the rib attachment point (on the centrums) migrates from the top  to the bottom of the centrum side as you go from the front of the rib cage to the back. So if you know enough you can tell where the backbone came from. However, I'll leave that to the guys in Alaska to figure out.

Here's two centrums hooked together. I was able to separate these with a bit of care. The big one on the bottom had a short, robust neural arch that was not blade-shaped in cross-section. Instead it is an oval cross-section, pretty robust.

 Here's a view of the prepared centrums I just sent to Alaska. The top group has 3  centrums as well as a nautilus, perched directly on the end of a centrum. Pretty cool! 


 Here's a centrun+neural arch that has the centrum rib attachment knobs on the side blending into the neural arch on the top. Must have come from the forward part of the rib cage. 
  And here is a rib with the neural arch that has no rib attachment knobs. Perhaps this came from the neck, where there are no ribs?
I still have 2 more backbones to finish preparing from this rock, and maybe more hidden inside it. Anyway, that's all there is for now. 
Sincerely, Greg Carr

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