Polygonia comma Polygonia comma Polygonia comma, the eastern comma, is a North American butterfly in the family Nymphalidae, subfamily Nymphalinae. This butterfly is seasonally variable. The upperside of the summer form's hindwings are all black, whereas the winter forms hindwings are reddish orange. The underside of both forms is striped with dark and light brown. There is a silvery comma mark in the middle of the hindwing in both forms. Its wingspan is . The eastern comma may be spotted in woods near rivers, ponds, marshes, swamps, and other water sources. This butterfly seldom visits flowers, but rather feeds on sap, rotting
Holdrian comma equal temperament are closer to Pythagorean tuning than that of 55. Thus Mercator's comma and the Holdrian comma are two distinct but related intervals. The name "Arabian comma" may be inaccurate; the comma has been employed mainly in Turkish music theory by Kemal Ilerici, and by the Turkish composer Erol Sayan. The name of this comma is "Holder koması" in Turkish. For instance, the makam "rast" (similar to the Western major scale) may be considered in terms of Holdrian commas: while in contrast, the makam "nihavend" (similar to the Western minor scale): has medium seconds between d–e, e–f, g–a, a–b,