Weren't pearl buttons "punched" out of the shell without breaking the whole
shell?
Keith Zeilinger
----- Original Message -----
From: "Martin H. Eastburn" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Saturday, September 26, 2009 11:16 AM
Subject: Re: [CONCH-L] Stump the conchlers: nautilus hickeys and Hepler's
violet snails
> I'd reconsider the position. My experience with brittle or in specific -
> glass. One can hit it with a rock or ball peen hammer and it shatters.
> Shoot it with a BB and a conical hole is produced. A high force over
> a small area can snap open a hole (e.g. a tooth point) whereas a broader
> surface bends and shatters.
>
> Martin
>
> Andrew Grebneff wrote:
>>> Curio shop Nautilus shells are frequently drilled by octopus, but I
>>> don't
>>> recall seeing any with two octopus holes. To my knowledge, Marion Nixon
>>> discovered shell-drilling by octopus (Journal of Zoology, 187:291-296,
>>> 1979).
>>>
>>
>> Holes made by octopuses are conical in section and are irregular in
>> plan view. They may show radular scratchmarks around the edges. I have
>> Oliva, Prunum ande Nautilus with clear octopus holes.
>>
>> Shells are brittle objects. Despite all the rubbish published about
>> fossil ammonoids showing tooth-punctures caused by mosasaur bites, an
>> shell will never show such damage... they can't. If something bites
>> them the shell will BREAK. Pieces may be broken out, but they will be
>> angular, never circular, and much more likely is that much of the
>> shell will shatter. The thicker the shell, the larger the pieces` will
>> be relative to the size of the shell.
>>
>> --
>> Regards
>> Andrew Grebneff
>> Dunedin, New Zealand
>> Fossil preparator
>> Mollusc, Toyota & VW van fanatic
>>
>> ----------------------------------------------------------------------
>> [log in to unmask] - a forum for informal discussions on molluscs
>> To leave this list, click on the following web link:
>> http://listserv.uga.edu/cgi-bin/wa?SUBED1=conch-l&A=1
>> Type your email address and name in the appropriate box and
>> click leave the list.
>> ----------------------------------------------------------------------
>>
>>
>>
>
> --
> Martin H. Eastburn
> @ home at Lions' Lair with our computer lionslair at consolidated dot net
> "Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer
> TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
> NRA Second Amendment Task Force Charter Charter Founder
> IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com/
>
> ----------------------------------------------------------------------
> [log in to unmask] - a forum for informal discussions on molluscs
> To leave this list, click on the following web link:
> http://listserv.uga.edu/cgi-bin/wa?SUBED1=conch-l&A=1
> Type your email address and name in the appropriate box and
> click leave the list.
> ----------------------------------------------------------------------
>
----------------------------------------------------------------------
[log in to unmask] - a forum for informal discussions on molluscs
To leave this list, click on the following web link:
http://listserv.uga.edu/cgi-bin/wa?SUBED1=conch-l&A=1
Type your email address and name in the appropriate box and
click leave the list.
----------------------------------------------------------------------
|
