Ümit,
There is no one standard whorl counting method. I prefer to count along the
suture, which gives 1/2 whorl more than does omitting the first semicircle.
There are other ways of doing it. I don't think anyone can reasonably argue
that one particular method is the "right" way of doing it. Just explain how
you did it if you write a paper.

An easy way to count the whorls of clausiliids & other tall shells is to
start from the aperture & go backwards; the body whorl will be #1,
penultimate whorl #2 & so on. This is useful if you only need to refer
especially to the lower whorls for whatever reason (see my paper on drill
holes in Turkish land snails).

Aydin

On Mon, 21 Feb 2005 09:55:04 +0200, umit <[log in to unmask]> wrote:

>Dear all,
>
>I noticed a difference in counting whorls when reading Likharev and
Rammelmeier (1952) "Lands Snails of....USSR" book. Normally when counting
whorls a -the first- semicircle of embyronic turn is omitted and 360 dgress
afterwards is accepted as 1 turn, so that 1st turn counted resembles
profile of a Nautilus. But in that book, i think, the semicircle is not
omitted and 1st turn counted ends where parallel to the median line of the
semicircle passes (total count is 1/2 turns less than the former). Is there
any other applications?
>
>The other question, when counting clausiliids a practical method is to
count whorls from the frontal view, i.g. mouth facing you. How do you count
similar slender snails like Subulinidae etc.?
>
>
>Best wishes
>
>Ümit
>
>
>

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