Andy, In the early 1990's I reconstituted genitalia dissections of Walker type specimens by Tams at the NMH London from more than 70 years prior that were stored in vials that were presumably dried out. The vial held some "gunk" at the bottom and a little paper label and that's it, no cover to the vial. I was pleasantly surprised that the genitalia was still intact. This was slightly different from slides made with glycerin and let to dry that I found at the CNC Ottawa. Not much work in reconstituting, but the whole thing was dried out and parts missing because the cover slips were just "sitting" on top of the structures. When the genitalia was present it was complete (soft bits not disintegrated). The danger is not in the glycerine in vials in my opinion, but how the vial is stored in relation to the specimen. It increases the possibility of NOT being able to match the dissection to the adult. I was unable to physically match other Tams dissections to adults. And of course, the concept of glycerine slides for long term storage should not be done (I would guess unless it is sealed with an adhesive). Alma Dr. M. Alma Solis Research Entomologist SEL, USDA, Smithsonian Institution P.O. Box 37012 National Museum Natural History, E-517, MRC 168 Washington, DC 20013-7012 Phone: 202-633-4573 E-mail: [log in to unmask] -----Original Message----- From: Entomological Collections Network Listserve [mailto:[log in to unmask]] On Behalf Of Andy Deans Sent: Wednesday, July 18, 2018 2:28 PM To: [log in to unmask] Subject: glycerol (and adhesive follow-up) Hi all, Does anyone know the history of glycerol / glycerin / glycerine use in entomology, for storing genitalia, etc.? I see references from the 1950s at least, some with additives like chloral hydrate and (yikes!) arsenic. Does anyone know how stable glycerol alone is over the long term? I heard anecdotally that there are specimens more than 100 years old that have been stored in glycerol. My impression is that these older specimens are mostly cuticle - the soft bits having been digested away with KOH. Would soft tissues preserve well in glycerol alone? Thanks for any help! Also, thanks for your responses to the survey about adhesives. I have been researching different classes of adhesives and now have a manuscript to be shared shortly. The results will also be presented at the meeting in Vancouver. More soon ... but I should put at least this advise out there now: We really should stop using clear nail polish and Elmer's! They are NOT archival. Andy Deans Frost Entomological Museum Penn State This electronic message contains information generated by the USDA solely for the intended recipients. Any unauthorized interception of this message or the use or disclosure of the information it contains may violate the law and subject the violator to civil or criminal penalties. If you believe you have received this message in error, please notify the sender and delete the email immediately.