Who was Zerach (seeing as he was not listed in Bereishis 46:10) among the sons of Shimon).
Rashi: Which is equivalent to 'Tzohar'
Why does the Pasuk omit the family of Ohad that is mentioned in Vayigash, Ibid.?
Which explains why only sixty-three families are listed here, as opposed to the seventy that went down to Egypt listed in Vayigash. See Sifsei Chachamim. Refer also to 26:36:2:1**. Rashi (citing the Yerushalmi in Yoma, 1:2): When Aharon died, the Clouds of Glory disappeared and the Cana'anim attacked them, they decided to return to Egypt and journeyed back eight Masa'os (six, according to Targum Yonasan in Devarim 10:6)