The skink-lizard honors boys, so it says: "May the boys be many, and may the girls be few!"
The sand-lizard honors girls and says the opposite: "May the girls be many, and may the boys be few!"
The curse of the sand-lizard makes the boys angry, so they throw stones at the sand-lizards, trying to kill them.
When one boy kills a sand-lizard, he says to another boy, "I've killed your slave!" This provokes the other boy, who kills another sand-lizard to avenge the death of his slave.
On and on it goes, and thus the boys kill many sand-lizards.
Inspired by: "Of the Lizards" in Tales, Customs, Names, and Dirges of the Tigre Tribes by Enno Littmann, 1915.
Notes: You can read the original story online. The author is not sure about the identification of the lizards, but he attributes the Seps chalcidica (three-toed skink) to the boys, and the Lacerta agilis (sand lizard) to the girls.