>Greetings CONCH-L,
>
>                               I have a rather simple (possibly dumb) question
>regarding the Operculum of Gastropods. When a book refers to an Operculum as
>being "horny" what exactly does this mean? I assume it means that the makeup
>of the Operculum is the same as a horn or antler because I've never seen any
>horn, spike, or protrusion on them before even under a microscope. I'm I even
>close? Thanks in advance.
>
>Steve McMahan
>
>
 
Horny means different things to different people.
 
For an operculum, it means that they are proteinaceous - that is,
uncalcified. For example, Polinices opercs are horny, Natica are calcified.
 
An excellent but rather detailed article on opercs just appeared:
 
Checa, A.G. & A.P. Jimenez-Jimenez. 1998. Constructional morphology, origin,
and evolution of the gastropod operculum. Paleobiology 24: 109-132.
 
This issue also has an article on the geometry of shells (computer-modeling)
and synchronized evolution in land snail lineages.
 
*  G Thomas Watters               *
*  Ohio Biological Survey &       *
*  Aquatic Ecology Laboratory     *
*  Ohio State University          *
*  1315 Kinnear Rd.               *
*  Columbus, OH 43212 USA         *
*  v:614-292-6170 f:614-292-0181  *
 
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