Albert Barnes Commentary Exodus 6:14

"These are the heads of their fathers` houses. The sons of Reuben the first-born of Israel: Hanoch, and Pallu, Hezron, and Carmi; these are the families of Reuben." — Exodus 6:14 (ASV)

These are the heads - We have in the following verses, not a complete genealogy, but a summary account of the family of the two brothers. Moses records for the satisfaction of Hebrew readers, to whom genealogical questions were always interesting, the descent and position of the designated leaders of the nation. See (Exodus 6:26–27).