According to the folk calendar - Basilisk

Basilisk is celebrated according to the folk calendar on June 4 (May 22, old style). On this day, the Orthodox Church honors the memory of Saint Basilisk of Koman, a martyr who suffered for his firm faith in Christ. The story of the Basilisk began in the 3rd century in Cappadocia (modern Turkey). He was the brother of Saints Eutropius and Cleonicus. When persecution began against Christians, the brothers were crucified on the cross, and Basilisk was sent into captivity in Comana. He was tortured and forced to make an offering to idols, but then thunder was heard and lightning flashed and destroyed the pagan idols. In anger, the ruler ordered the Basilisk to be beheaded. People believed that there was a huge snake with a rooster's head, a toad's body and a snake's tail. The monster was called the Basilisk and it was said that it emerged from an egg laid on January 15th by a black 7-year-old rooster, hatched in a swamp by a toad and hatched just on June 4th. The snake attacked settlements, ate livestock, destroyed grain crops, and dried up wells and springs. To prevent the appearance of a destructive snake, residents on a given day collected all the chicken eggs and boiled them for a long time. Black roosters were also not favored; they were slaughtered before they were 7 years old. And if on the day of the Basilisk they met an egg on the road, they would bypass it or destroy it; they were forbidden to take it home, otherwise they could invite trouble. The peasants believed that it was not worth working in the fields and vegetable gardens on this day, since only weeds, wormwood and cornflowers could grow from the planted crops. Therefore, the residents switched to household chores, and in the evening they got together, talked, shared jokes and stories. Sometimes the day was called Nightingale. In the morning, people came to listen to the nightingale sing. It was also considered shameful to catch a nightingale, since they believed that its appearance in human habitation foreshadowed wealth and prosperity. Bird hunters went into the forest to catch nightingales. Caught birds on Nightingale Day were considered especially valuable. On this day, the girls went to the pond and told their fortunes. To do this, they wove wreaths from birch branches and put them on the water. If the wreath floated away and did not sink to the bottom, it means that happiness awaited the girl. Noticing abundant dew on the Basilisk, residents prepared for a good harvest in the fields and vegetable gardens. The thick fog promised a lot of mushrooms after the rain. The singing of a nightingale in the middle of the night was heard on fine days. If many spiders and flies were observed that day, the cucumber harvest was expected to be rich.