ἐνίοτε οἱ οἰκέται εἰς τὴν θάλασσαν ἐλαύνουσιν αὐτούς → sometimes the slaves ride them into the sea
att. p. οὗτινος, gén. de ὅστις.
ὅτου v.s. ὅστις
for the genitive case of ὅστις (as adverb); during which same time, i.e. whilst: whiles.
ὅτου: (= οὗτινος) gen. к ὅστις.