… lower to almost the knees when the cuirasse bodice and Princess sheath took over the fashion ideal. The lifting tournures and bustles of the mid 1870’s suddenly shifted to a lower position around 1880 so the fullness was not specifically over the rear end (although decoration and draping gave fullness there) for the undergarments.
This is the noteworthy feature which designates a short 3 year and short lived period called “Natural Form”.
(photo: modern interpretation of Natural Form style showing the low draping and fullness in the back)