I have some 'rollers' that are large - the size of my hand.  Looking at
  the other shells, it appears that the lip and fingers (on that kind)
are grown and are functional.  Then a growing need comes and
the bulk is dissolved off and another whorl is put on.  Often leaving a jagged
line on the 'cone' as another wrap is applied and more lips/fingers are applied.
I think it is like a snake molting its skin or antlers on deer / elk.  Shed each season.

Do I have my observations in line ?

Martin

--
Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
"Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer
TSRA: Endowed; NRA LOH&  Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Originator&  Charter Founder
IHMSA and NRA Metallic Silhouette maker&  member. http://lufkinced.com/

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