avers[1] that these fireflies are the ghosts of the old Minamoto and Taira warriors; that, even in their insect shapes, they remember the awful clan[2]-struggle of the twelfth century; and that once every year, on the night of the twentieth day of the fourth month, they fight a great battle on the Uji River. Therefore, on that night all caged fireflies should be set free, in order that they may be able to take part in[3] the contest.
The Genji-botaru is the largest of Japanes fireflies,—the largest species, at least, in Japan proper,[4] not including the Loochoo Islands. It is found in almost every part of the country from Kyūshū to Ōshū. The Heike-botaru ranges further north, being especially common in Yezo; but it is found also in the central and southern provinces. It is smaller than the Genji, and emits a feebler light. The fireflies commonly sold by insect-dealers in Tōkyō, Ōsaka, Kyōto, and other cities, are of the larger species. Japanese observers have described the light of both insects as "tea-coloured" (cha-iro),—the tint of the ordinary Japanese infusion, when the leaf is of good quality, being a clear greenish yellow. But the light of a fine Genji-firefly is so brilliant that
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