The surname in Polish is Żarnowski for males and Żarnowska for females. The first letter Ż is different from Z in English; the last letter changes with gender: i for males, a for females. But as immigrants got farther away from their roots, simple Zarnowski was often used for both men and women.
Joseph Żarnowski was born about 1908, exact details unknown. His parents migrated to the United States. Nothing further is known about him.
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