The straight leg bush jeans were actually designed and sold by Levi's in the 60s and can be seen in the 60s tv show, Mod Squad, with Linc Hayes wearing them. As the story goes, when Levi's had their tax accountants on the job in the 70s, they located an entire warehouse full of left over and unsold straight leg bush jeans from the 60s. Apparently they'd forgotten/'lost' any knowledge of said jeans. So, they took the lot of them and washed them, and these were the very first 'pre-washed' jeans ever on the market in the US. Some were bleached and others were left quite dark, but they had to be washed to be able to be sold. They'd been sitting in that warehouse for about eight years.
Of course, Levi's charged a higher price than for the usual, rigid, unwashed, regular jeans and due to the novelty of the cut as well as the 'pre-wash', they sold like crazy and henceforth, Levi's redesigned them with wide bell-bottoms for the newer 70s version. Having worked in a shop that sold these jeans, I was lucky enough to be able to purchase two pairs of the straight leg 60s version, and still own them, as well as two pairs of the bells, though I preferred the straight ones. Still own them all!
Saw a pair of the bells on eBay recently up for $295. If only the execs at Levi's had a clue on what they're missing out on. Wishing they'd bring these babies back and not as the silly mini-skirts that they currently have in the stores.