<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body text="#000000" bgcolor="#FFFFFF">
<div class="moz-cite-prefix">Dear Rebecca,<br>
<br>
completely agree with Charlie. As long as you don't have any
climate control issues in your collection that could trigger mould
issues, I would leave the dry specimens in the jar as they are.
Especially in old historic specimens it is not always clear which
type of preservation fluids were used for initial
preparation/fixation. There is a whole variety of historic
fixatives, some of them include heavy metal salts such as mercury
in rather high concentrations (these were often used e.g. for
preparations of marine invertebrates). If you don't know the
history of preservation/fixation methods in your collection, I
would be very careful in handling these specimens. Have in mind
that prevailed usage of formaldehyde fixation/preservation starts
roughly around 1910. Dried ethanol specimens may look rather poor
(not initial fixation, only ethanol preservation = +/- dehydration
of specimens to a certain extent). Be careful if your specimens
have been prepared prior to 1900 and still look +/- good or show
some salty incrustations on the specimens, which could be an
indicator for historic fixatives other then formaldehyde.<br>
<br>
Rehydration will not restore the their original shape of
specimens. If rehydration is necessary, I would also recommend
method Simon Moore suggested in a previous NHCOLL-L posting (see
below). For specific questions it might be worth contacting Simon
directly. <br>
<br>
<br>
All the best<br>
Dirk<br>
<br>
*************<br>
<font id="role_document" face="Arial" size="2" color="#000000"><font
family="SANSSERIF" ptsize="10" face="Arial" lang="0" size="2">From:
Simon Morre, <a class="moz-txt-link-abbreviated" href="mailto:couteaufin@btinternet.com">couteaufin@btinternet.com</a></font></font><br>
<font id="role_document" face="Arial" size="2" color="#000000"><font
family="SANSSERIF" ptsize="10" face="Arial" lang="0" size="2">Sent:
21/08/2011 12:00:02 GMT Daylight Time<br>
Subj: Re: [NHCOLL-L:5600] FW: Rehydration of a sea anemone</font></font><br>
<br>
<font family="SANSSERIF" ptsize="10" face="Arial" lang="0"
size="2"><font style="BACKGROUND-COLOR: transparent"
face="Arial" size="2" color="#000000"><font face="Arial"
size="2" color="#000000">
<div>Always rather ticklish when you have the holotype to
perform such a radical treatment!</div>
<div>Bear in mind also that rehydration will improve the
appearance and texture but it will compromise future DNA
extraction/readings. If you need further advice on this
let me know.</div>
<div>I have also forwarded this to John Simmons who may also
have some comments.</div>
<div> </div>
<div>I tend to use Decon-90 at around 3 to 5% in deionised
water as a rehydrating agent.</div>
<div>The reaction is catalysed by warming it to no more than
50 deg. Centigrade (hotplate) and make sure that the
container has a loose lid to prevent massive evaporation
during warming.</div>
<div>Obviously photograph and weigh the specimen prior to
treatment.</div>
<div>Start the process first thing as it can take some time
and so that you can monitor its progress during the day.
</div>
<div>The fluid will start to yellow a bit and may smell
rather fishy; the specimen will gradually sink into the
fluid - this will only happen in an ideal situation, so if
the specimen has expanded and feels soft and more flexible
like it should if not dry, then it will have reached its
'end-point'. If it's still floating then it will have air
trapped inside.</div>
<div> </div>
<div>In which case.... place the specimen in clean water and
place the container inside a vacuum desiccator. Apply a
mild vacuum to it and air should bubble out of the
specimen. After no more than a minute, stop the pump
(making sure that the hose is removed from the desiccator
and that the tap is closed <strong>before</strong> the
pump is switched off - or it will suck the oil from the
pump all over the specimen!!)</div>
<div>Then release the vacuum slowly and the anemone should
sink completely or partly. Repeat the process until no
more air bubbles out. Small amounts of trapped air will
often slowly diffuse out later in the alcohol preservative
(see below).</div>
<div>You should now have a fully rehydrated specimen. Place
into formalin to refix overnight and next day start to
transfer into an alcohol dehydration ladder so that by the
end of the day, the specimen is preserved in IMS once
again. Ensure that the jar seal is good! Finally, make a
note of the treament for the specimen's record and reweigh
the specimen, having drained off excess fluid and
re-photo.</div>
<div> </div>
<div>That should hopefully be it!</div>
<div> </div>
<div><font family="SANSSERIF" ptsize="10" face="Arial"
lang="0" size="2">With all good wishes, Simon<br>
<br>
Simon Moore MIScT, FLS, ACR,<br>
Conservator of Natural Sciences,</font></div>
</font></font></font><br>
<br>
<br>
Am 04.01.2013 05:34, schrieb <a class="moz-txt-link-abbreviated" href="mailto:CSTURMJR@pitt.edu">CSTURMJR@pitt.edu</a>:<br>
</div>
<blockquote
cite="mid:f3022b57df9f0ee79fe701819371fd6a.squirrel@webmail.pitt.edu"
type="cite">
<pre wrap="">Rebecca,
I will not opine on how to test what solution may have been used to store
the specimens, however, I will question why you might want to rehydrate
them. Unless there is a specific need to rehydrate a specimen, I would
advocate to leave them in a dessicated state. The specimen is already
dessicated and as such will probably stay that way for a long time (unless
something is done to it). Rehydration methods can adversely affect a
specimen. Better methods may be available in the future. Unless there is a
need to rehydrate the specimen for a current study, store it dry. I have
attached a chapter that I wrote six years ago and there are some
references in Section 5.9 that you might like to read before rehydrating.
</pre>
<blockquote type="cite">
<pre wrap="">Hello all,
We have several old collections in the park without any information about
how they were prepared. Many need to be rehydrated and rehoused into
better storage. Is there a simple test to determine what they are/were
preserved in before we rehydrate?
thank you
--
Rebecca Cole-Will, Cultural Resources Program Manager ~ Acadia National
Park, 20 McFarland Hill Drive, PO Box 177, Bar Harbor, ME 04609
~207.288.8728 ph., 207.288.8709 fx.
_______________________________________________
Nhcoll-l mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Nhcoll-l@mailman.yale.edu">Nhcoll-l@mailman.yale.edu</a>
<a class="moz-txt-link-freetext" href="http://mailman.yale.edu/mailman/listinfo/nhcoll-l">http://mailman.yale.edu/mailman/listinfo/nhcoll-l</a>
</pre>
</blockquote>
<pre wrap="">
Regards,
Charlie
.................................................
Charlie Sturm
Treasurer
American Malacological Society
Research Associate - Section of Mollusks
Carnegie Museum of Natural History
Pittsburgh, PA, USA
Associate Professor - Family Medicine
Fellow-American Academy of Family Practice
Fellow-Academy of Wilderness Medicine</pre>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
Nhcoll-l mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Nhcoll-l@mailman.yale.edu">Nhcoll-l@mailman.yale.edu</a>
<a class="moz-txt-link-freetext" href="http://mailman.yale.edu/mailman/listinfo/nhcoll-l">http://mailman.yale.edu/mailman/listinfo/nhcoll-l</a>
</pre>
</blockquote>
<br>
<br>
<pre class="moz-signature" cols="72">--
Dirk Neumann
Tel: 089 / 8107-111
Fax: 089 / 8107-300
email: Dirk.Neumann(a)zsm.mwn.de
Postanschrift:
Staatliche Naturwissenschaftliche Sammlungen Bayerns
Zoologische Staatssammlung München
Dirk Neumann, Sektion Ichthyologie / DNA-Labor
Münchhausenstr. 21
81247 München
Besuchen Sie unsere Sammlung:
<a class="moz-txt-link-freetext" href="http://www.zsm.mwn.de/ich/">http://www.zsm.mwn.de/ich/</a>
---------
Dirk Neumann
Tel: +49-89-8107-111
Fax: +49-89-8107-300
email: Dirk.Neumann(a)zsm.mwn.de
postal address:
Bavarian Natural History Collections
The Bavarian State Collection of Zoology
Dirk Neumann, Section Ichthyology / DNA-Lab
Muenchhausenstr. 21
81247 Munich (Germany)
Visit our section at:
<a class="moz-txt-link-freetext" href="http://www.zsm.mwn.de/ich/">http://www.zsm.mwn.de/ich/</a>
</pre>
</body>
</html>