In reply to:

Mammatus Clouds - Rounded, smooth, sack-like protrusions hanging from the underside of a cloud (usually a thunderstorm anvil). Mammatus clouds often accompany severe thunderstorms, but do not produce severe weather; they may accompany non-severe storms as well. See Figs. 3 (HP storm), 5 (LP storm), and 7 (supercell).

It shure sounds like mammaries to me.