Hi Oliver:
Of course I encounter those difficulties. In many cases, even when the
species determination in the books (catologues for example) are based in
shell caracteristics, many of them are as you say color or sculpture
that in many circumstances have dissapeared with the past of thousend of
years. Thats why I have a reference collection, both of fresh an
archaeological specimens in different stages of dissolution, for study
which traits remain and which not, or in the most cases, some remain in
certain conditions, and others in other.
You mencioned you have many Pectinids. Have you a "system" (I donīt know
how to put it in english) to describe their different parts? Another
problem I confront is that the vocabulary to describe the parts of the
shell itīs offen not enough, because I need to describe many points in a
single "part" (for describing the manufacture and use of the artifact).
Dou you have references (hopefully in internet please) of different
systems of description?. I use Keen 1971.
Regards
Marcela Lucero
Olivier Caro wrote:
> Dear Marcela
>
> Here, I learned something.
> But that's terrific! Most of times, when I remember my little
> experiments, the fossilized shells lack any colour, excepted maybe in
> sandy layers when they are protected by a stony roof - and over any
> water. As the pattern often helps for determination, I prefer not to
> imagine the difficulties you encounter. Arghll... I often found some
> Lucinidae and Trochidae in the bush in western Crete, in old "minoan"
> earthquaked harbours full of goats crunching the shells, and most of
> times, was unable to determine more than the genus.
> The muscle scars are of some help, I suppose, when their are not too
> badly damaged by the organic cover.
> Here in France, we have two venerids extremely close one to each
> other: decussatus and philippinarum.
> After 20 years of collecting these two species, I stay unable to make
> the difference, even after having received complete explanations from
> specialists.
> Put these two species in the ground during let's say 12000 years, and
> you extract just one species, even if you knew that some specimens
> came from Philippines when other ones were native. What a job!
>
> Olivier Caro
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