Scott donated stock back, at generation 41, to repopulate the colony. The progeny of these are now termed BALB/cJ and, as of 14 December 2006, were 221 generations from the founding stock.
To repopulate the colony, Scott donated stock at generation 41. These descendants are now referred to as BALB/cJ, and as of December 14, 2006, they had reached 221 generations since the founding stock.