Aydin (and any others),

In an attempt to keep the "blurb" of data short,
some things were held back.

Yes, the distribution is normal (it is viewable
at http://www.cowrys.org/research/hlvteeth.htm ).
The C. helvola average labial tooth count is 15.5 and
its standard deviation is 1.33 teeth. On a line, it
looks like this (with std. dev. above the line and
labial tooth count below the line):

  -4    -3    -2    -1     M    +1    +2    +3    +4
---^-----^-----^-----^-----^-----^-----^-----^-----^---
^12     ^13     ^14     ^15 16^     17^     18^     19^

The estimate of four std. dev. out is close for not
knowing the mean and std. dev.! The shells with 11 and 20
labial teeth are beyond the 5th std. dev. point, so there
may _not_ be a possibillity of 10 or 21 labial teeth (in
Hawaii, anyway. Who knows what is possible elsewhere?

Although I think my sample of C. helvola is fairly
representative of Hawaii, my samples of other species
from Hawaii are much smaller and cannot be expected to
contain ALL of the possibile labial tooth counts, so I
"inflated" some populations to see what might be likely.

A few ideas are yet to be fleshed out concerning C. helvola
but most of the tooth count data are posted. A nagging
mystery is why the difference between the labial & col-
umellar counts on these specimens fits the normal curve
best of all yet the columellar tooth count fails (badly)
in matching a Gaussian distribution.

Aloha,

makuabob (a.k.a. Bob Dayle)

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