At 02:30 PM 6/26/98 -0500, you wrote:
>     Can you more experienced conchologists/malacologists out there
>     help me with a few questions concerning the age of shells.
>
>     1) I was wondering how long it takes most cones and cowries to
>     reach their adult size?  That is when the shell is considered
>     adult and no longer juvenile.
>
>     2) Can you determine the age of a shell?  I know with some
>     bivalves, you can count the number of growth lines to determine
>     its age.  How do you tell the age of gastropods such as cones or
>     cowries?
>
>     3) Are giant sized shells very old shells or are they ones which
>     just grew bigger?
>
>     Thanks in advance for any and all responses.
>
>     Ted Hu
>     Montebello, California USA
>
Ted, I'm not sure about all species but all of the Lambis show old age by
the marked thickening of the lip.
Horatio