Hi Paul,

Maybe they are nail holes. Perhaps someone hung the shells on a string.

Alan


On Fri, 25 Sep 2009, Paul Callomon wrote:

> Hi Alan,
>
> These don't seem to be drill holes; they are more like simple punctures, as if you had driven a nail into the shell. They are also invariably in pairs, one on either side of the shell. Perhaps Conchlers could look at the Nautilus shells in their own collections and see whether they can find the same thing?
>
> PC.
>
> Paul Callomon
> Collections Manager
> Malacology, Invertebrate Paleontology and General Invertebrates
> Department of Malacology
> Academy of Natural Sciences
> 1900 Parkway, Philadelphia PA 19103-1195, USA
> Tel 215-405-5096
> Fax 215-299-1170
> Secretary, American Malacological Society
> On the web at www.malacological.org
>>>> Alan Kohn <[log in to unmask]> 09/25/09 5:34 PM >>>
> Hi Paul (et al.),
>
> 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). She also observed that the characteristic size and markings of the holes could not be the work either of the radula or the beaks, and she demonstrated that the structure responsible is the cuticularized papilla of the posterior salivary gland. She illustrates the holes and that organ in her paper, and she also had a paper in Malacologia the same year (18:431-434) and another, also on drilling gastropod shells, in J. Zool. 216:687-716, 1988. Both of these papers also illustrate the holes. She also had two other papers on octopus hole drilling in J. Zool. (191: 75-88, 1980, and 196: 439-444, 1982), but I don't seem to have reprints of those.
>
> I suspect most if not all octopus are capable of shell drilling (Roland Anderson might know). Our big octopus here (O. dofleini) certainly drills gastropods (e.g. Polinices lewisi) to inject its venom, and I think it also drills.
>
> Alan
>
>  ----- Original Message -----
>  From:   Paul Callomon
>  To: [log in to unmask]
>  Sent: Friday, September 25, 2009 11:33   AM
>  Subject: [CONCH-L] Stump the conchlers:   nautilus hickeys and Hepler's violet snails
>
>  Folks,
>
>  Two headscratchers for the Conch-L Geezers on the Bench:
>
>  1) I have been sorting out some Nautilus specimens and find that many of   them bear a pair of puncture marks, one on each side of the body chamber.   These are about 1 or 2 mm across, and often slightly square or diamond-shaped.   They go right through the shell, though there is no cracking or spalling,   suggesting that the critter was in there and providing some support at the   time. Some specimens show signs of having healed previous such holes. "Fish   bites" I thought; perhaps something with a small number of opposed teeth like   a Napoleon Wrasse? Someone suggested they might be marks from traps of some   kind, though, so I thought I'd see if anyone can enlighten me/us, preferably   with reference to literature.
>
>  2) We are spiffing up Neil Hepler's great Janthina exhibit for this   year's Philadelphia Shell Show. Does anyone remember seeing it the first time   round, probably in the 1970s? If so, could you tell me when, and (for ten more   points) where?
>
>  PC.
>
>
> Paul Callomon
> Collections Manager
> Malacology,   Invertebrate Paleontology and General Invertebrates
> Department of   Malacology
> Academy of Natural Sciences
> 1900 Parkway, Philadelphia PA   19103-1195, USA
> Tel 215-405-5096
> Fax 215-299-1170 <[log in to unmask]>
>

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