Dear Joe;-
    I understand the dieing out of Hormatoma----but did it do so without
branches, descendants, etc.? It appears nothing like  a "Slit-Shell", but very
much like slim coiled families----Terebra, Epitoniidae, Miters, etc.
        Art

Joe and Nora wrote:

> Hello Art,
>
> Joe here. I sifted through my collection and literature. All of our
> 'Hormotoma' specimens are Ordovician or Silurian in age. This is mostly a
> North American fossil (although also found 'rarely' in Europe). It was
> usually placed (despite its outward appearance) until the 1940's  in the
> superfamily Pleurotomariacea by some authors. Its kin, Mourlonia, somewhat
> resembles descendents through to the Pleurotmaria.
> Subsequesnt authors do not place it in this superfamily but place it  in
> agroup archaeogastropods with no further lineage. It is thought to die out
> in the Silurian. It is thought by most to have no relationship with the
> modern pleurotomaria.
> Most authors ( some exceptions) do not accept any known antecedents of the
> modern Pleurotomaria until the Mesozoic age.
> Your species 'gracilis' was first placed in the genus  Murchisonia (Hall,
> 1847) and subsequently changed by the author to Hormotoma sometime in the
> 1850's (I 'think').
>     Nora and I just obtained a scanner and it is surprising how well it
> scans small fossils. Sometime in the not too distant furue we'll scan some
> paleozoic gastropods, mesozoic pleurotomaria, etc. and make them accessible
> to Conch-L subscribers to view.
>
> Original Message -----
> From: "Art Weil" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Tuesday, November 14, 2000 7:34 PM
> Subject: Hormotoma
>
> > Dear (probably Old Seashells and Andy);-
> >         What I have here is a Hormotoma gracilis (maybe Homotoma?). It
> > measures 13.48mm long and is about 400 million years old. Since a
> > fleeting glance makes it look like an Epitonium (or Cerith or other
> > coiled critter) I wondered if there is some descendency from the fossil
> > that I have. Inquiring minds want to know.
> >             Art