Swallowtail butterfly black swallowtail is the state butterfly of Oklahoma. Swallowtail butterfly Swallowtail butterflies are large, colorful butterflies in the family Papilionidae, and include over 550 species. Though the majority are tropical, members of the family inhabit every continent except Antarctica. The family includes the largest butterflies in the world, the birdwing butterflies of the genus "Ornithoptera". Swallowtails have a number of distinctive features; for example, the papilionid caterpillar bears a repugnatorial organ called the osmeterium on its prothorax. The osmeterium normally remains hidden, but when threatened, the larva turns it outward through a transverse dorsal groove by inflating it with fluid.
Comma bacon, eggs, toast and marmalade, and tea"). "The Chicago Manual of Style", and other academic writing guides, require the serial comma: all lists must have a comma before the "and" prefacing the last item in a series. If the individual items of a list are long, complex, affixed with description, or themselves contain commas, semicolons may be preferred as separators, and the list may be introduced with a colon. In news headlines, a comma might replace the word "and", even if there are only two items, in order to save space, as in this headline from Reuters: Commas are often