Abstract
Chrysozephyrus ataxus is widely but locally distributed in southern parts of Japan, and is also known from Tsushima Island. The author collected the eggs of this species from that Island in the spring of 1958, and succeeded in having 10 males and 10 females of butterflies by breeding. Consequently he found the following difference between the specimens from Tsushima Island and those from other parts of Japan. Male: Upperside. Black margins of both wings are narrower, especially near the anal of the hind wing. Female: Upperside. Purple patch of the forewing is generally larger than that of subsp. kirishima-ensis OKAJIMA, but smaller than that of subsp. yakushimaensis YAZAKI. Underside; Markings are the same as those of other localities in both sexes.
