Here is my two cents worth on the atlantic dogwinkle.
 
In the area where I collect here in south central Maine I find all
different color variations - yellow, brown, orange and white and striped.
These colorful ones I find in the intertidal zone mostly underneath large
overhanging rocks. Maybe the overhanging rocks help the brightly colored
ones escape predation by gulls? Once you reach the low tide mark (irish
moss territory) and where the coraline starts to coat everything not nailed
down the N lapillus seem to be almost 100% white, a dirty scuffy white.
Also their spires seem to be more elongate then the ones above the high
tide mark.
 
  I have found more rough or scaled versions also but their occurence
doesn't seem to correlate in anyway to the amount of wave action the
location receives (quiet inlets compared to rough headlands).  What about
on the West cost of the US?  Does the occurence of very scaled/frilled
versions of Nucella lima correlate to environment in anyway?  What about
color variations?
 
Beth DeHaas
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