Danaides
2 of the 7 encyclopedias on this shelf carry an entry for Danaides. Both are reproduced below, so you can see where they agree and where they differ.
1000 Classical Characters (1900)
The fifty daughters of Danaüs, king of Argos, who married the fifty sons of their uncle Aegyptus . Danaüs had been told by the oracle that he would be killed by a sonin-law, and he made his daughters promise to slay their husbands immediately after marriage. All of them fulfilled their father's wishes except one, Hypermnestra , who spared her husband Lynceus . Danaüs. Son of Belus , and twin-brother of Aegyptus. Belus had assigned Libya to Danaüs, but the latter, fearing his brother and his brother's sons, fled with his fifty daughters to Argos. Here he was elected king by the Argives in place of Gelanor, the reigning monarch. The story of the murder of the fifty sons of Aegyptus by the fifty daughters of Danaüs (the Danaides) is given under Aegyptus. There was one exception to the murderous deed. The life of Lynceus was spared by his wife Hypermnestra; and according to the common tradition he afterwards avenged the death of his brothers by killing his father-in-law, Danaüs. According to the poets the Danaides were punished in Hades by being compelled everlastingly to pour water into a sieve. From Danaüs the Argives were called Danai, which name, like that of the Argives, was often applied by the poets to the collective Greeks. Danubius (Danube, in German Donau). Called Ister by the Greeks, one of the chief rivers of Europe, rising in M. Abnoba, the Black Forest , and falling into the Black Sea after a course of 1770 miles.
Aiton's Encyclopedia (1910)
da-na'i-dez, in Greek legend, the fifty daughters of Danaus. They accompanied their father to Argos, but were followed thither by the fifty sons of Aegyptus, who sought them in marriage. The father consented to the marriage, but provided each daughter with a dagger, commanding her to murder her husband. They all obeyed except Hypermnestra, who allowed Lynceus, her husband, to escape. The Danaides were purified from their crimes by order of Zeus. Nevertheless, so the legend runs, they were punished for it after death, for in Hades they were doomed to draw water in sieves forever. See Danaus