Polygonia comma form of comma is frequently confused with the dark form of the question mark ("P. interrogationis"), but the two can readily be distinguished by the shape of the comma mark on the underside. The pale form is easily confused with the satyr comma ("P. satyrus"), which usually occurs north and west of the eastern comma's range. They can be distinguished by the upperside color, which is orange brown in the comma and tawny yellowish brown in "P. satyrus"; by the underside pattern, which tends to be mottled in the comma but appears to be more longitudinally streaked in "P. satyrus";
Punctuation and the "exclamation comma". The "question comma" has a comma instead of the dot at the bottom of a question mark, while the "exclamation comma" has a comma in place of the point at the bottom of an exclamation mark. These were intended for use as question and exclamation marks within a sentence, a function for which normal question and exclamation marks can also be used, but which may be considered obsolescent. The patent application entered into the national phase only in Canada. It was advertised as lapsing in Australia on 27 January 1994 and in Canada on 6 November