Pausanias Description of Greece 1.43.4

[4]
  Between this and the hero-shrine of Alcathous, which in my day the Megarians used as a record office, was the tomb, they said, of Pyrgo, the wife of Alcathous before he married Euaechme, the daughter of Megareus, and the tomb of Iphinoe, the daughter of Alcathous; she died, they say, a maid. It is customary for the girls to bring libations to the tomb of Iphiaoe and to offer a lock of their hair before their wedding, just as the daughters of the Delians once cut their hair for Hecaerge and Opis.

[4] Proceeding from there to the hero-shrine [ hērōion] of Alkathoos, which in my day the people of Megara used as a place for the safe-keeping [ phulakē] of written-records [ grammata], was the tomb [ mnēma], they said, of Pyrgo, the wife of Alkathoos before he married Euaikhme, the daughter of Megareus, and the tomb of Iphinoe, the daughter of Alkathoos; she died, they say, a still a virgin [ parthénos]. It is customary for the girls [ korai] to bring [ pros-pherein] libations [ khoai] to the tomb [ mnēma] of Iphinoe and to make-an-offering [ ap-arkhesthai] of their [cut] hair before their wedding [ gamos], just as the daughters of the people of Delos once cut their hair for Hekaerge and Opis.