Hello Nancy:
As John Cramer stated melanism occurs in many genera.
I imagine that if you looked long and hard enough and in enough places most
every genera would provide a malanistic form.
In my collections I have found them in most major families myself, including
many Bivalvia species.

Rostratism may be more a Cypraea issue from what little I've seen.
I do not know how it would translate into appearance in other non-ovulid
gastropods.
Unless somehow you could count the natural formation which protrudes beyond
the stromboid notch on Strombus gastropoda.
Perhaps Marginellids could develop rostration also... Check with Bob Lipe on
that one.

New Caledonia is known for their melanistic and rostrate forms.

I can not provide any feed back on the physiology aspects on either.

Leslie Allen Crnkovic
HARF/IMCS




-----Original Message-----
From: Conchologists of America List [mailto:[log in to unmask]]On
Behalf Of Nancy Smith
Sent: 05 September, 2000 8:13 AM
To: [log in to unmask]
Subject: melanism

Hello all,

I sent this over the weekend but I'm not sure it was rec'd by the
list.  So, I'm sending again.  In case it was specifically ignored, then go
for that Delete button.  ;)

Q:   I know that sometimes melanism (and rostration) occurs in Cypraea.
Does
it occur (mainly melanism but stretch the question to include rostration as
well) in other families too?   If not, why?

Nancy