Tip - About Clam Chowders Regional Variations

About chowder's regional variations, it is wiser to be cautious.  As
various mythologists have had it, Maine calls for lobster bodies as a
base to give chowder flavor; New Hampshire wavers between clam and
fish, but eschews all vegetables; Massachusetts allows potatoes and
onions, but eschews the tomato (Cape Cod further waxes vociferously in
favor of steamer over quahog); coastal Rhode Island rejects not only
the newfangled tomato but the newfangled milk, while Connecticut,
contaminated by its proximity to Manhattan, allows tomatoes, but
retains some grace by otherwise fixing its chowders in the traditional
New England manner.

John Thorne, from "Serious Pig: An American Cook in Search of His
Roots"