With an electric mixer on medium speed, beat egg whites and sugar with orange peel and baking powder until blended. Gradually add nuts and flour, beating until mixture is thoroughly blended. Cover and chill until firm enough to handle, at least an hour or up to a day.
Lightly flour your hands and pinch off a three-tablespoon size piece of dough. On a lightly floured board, use the palms of both hands to evenly roll an 8-inch (20 cm) long rope. Cut rope in half; roll each half out again to 8 inches (20 cm). Fold an inch of each end back onto rope and pinch ends to make bone shapes. Repeat to shape all the dough.
Place bones an inch apart on a buttered and flour-dusted baking sheets. Bake at 325 degrees F (165 degrees C) for about 20 minutes until cookies are lightly browned on bottoms.
