Section 43. Between March first and October thirty-first, both dates inclusive, in any year, the director may authorize the taking or possession of egg-bearing lobsters by any person licensed under section thirty-eight to catch or take lobsters and edible crabs, upon the condition that such egg-bearing lobsters shall be taken, held or delivered in accordance with the instructions of the director to a plant for the propagation of lobsters established and maintained for rearing them from the time of hatching to the bottom crawling stages or for such other disposition as the director may deem for the best interests of the commonwealth. If the eggs from the lobsters so obtained shall be hatched the young therefrom shall be reared to the bottom crawling stages. Lobsters from which eggs have been so hatched, and the young lobsters so reared, shall be liberated, as nearly as possible, in the areas from which such egg-bearing lobsters were obtained and in the same proportion. Nothing in this section shall be so construed as to prevent the director from otherwise disposing of lobsters from which eggs have been so removed, or young lobsters so reared, when in the opinion of the director by so doing depleted or non-productive areas may be benefited.