Coral or Bryozoan

[grg1109]

Middle Devonian, Finger Lakes region,  Hamilton Group, both are "branching forms".  Today I found what I at first thought was a colonial rugose coral Eridophyllum(1st photo by someone on another forum).  The outside appearance looks to me to be very simalar to what I found(3rd photo).  However, on closer inspection, I realized that the open ends were quite different.  In his you can see septa...on mine the inside of the ends are "grainy"(2nd photo).  Also it should be noted that mine has been broken at the upper sections.  It's been suggested that mine might actually be Bryazoa.  Any thoughts?

Thanks

Greg

 

 

Edited April 26, 2021 by grg1109

[Rockwood]

I think this is a colonial rugose coral. I doubt the preservation is good enough to refine that identification however. 

The variation in diameter tends to support coral over bryozoan.

Edited April 26, 2021 by Rockwood

[grg1109]

The more noticable "rings" sudden angles and smaller less noticable "hatch like markings"  match those of the colonial rugose coral Eridophyllum.  The diameter also falls within this description in Wilson's book.   What I can't reconsile is that I don't see septa at the ends...mine are more of a "granular" nature.  I'm wondering if it is because mine seems to appear to be from the middle or lower section(completly missing the top) of the Colony...while the first example appears to be the top or end section of the colony?

Greg

Edited April 26, 2021 by grg1109

[mikeymig]

Branching Colonial Rugose Coral - Eridophyllum subcaespitosum.

[grg1109]

2 hours ago, mikeymig said:

Branching Colonial Rugose Coral - Eridophyllum subcaespitosum

What about it makes you believe this?  I'm asking so that I will understand...not challenging you.

Thanks

Greg

[ClearLake]

During the fossilization process yours have been recrystallized and that appears to have erased most details on the inner parts of your corals.  the original material that made up the coral has been replaced by crystalline calcite (probably) which gives the "grainy" texture.  That's what happens after a couple hundred million years!!

[mikeymig]

18 minutes ago, grg1109 said:

What about it makes you believe this?  I'm asking so that I will understand...not challenging you.

Thanks

Greg

Ha its okay, you can challenge me. I've collected thousands of fossil corals in NY over the past 30 years. Most of my work is in the Devonian and I have amassed a huge collection of fossil corals. Your specimen is "fresh" and is still covered in shale but the habit, structure, locality, and age indicate Eridophyllum. You suspected that with your own research and you were right. Now you just have to remove the other pieces and see if you can reassemble it. There are only so many different types of fossil corals of the Devonian of NY. Process of elimination. Have fun.

[grg1109]

Ok, I get it ...Thanks very much!

Greg