Egg masses; the direction they spiral

This is an interesting question as their is some evidence to suggest that some floating siphonophores such as Bluebottles or Portugese man o'war (Physalia) and the related Velella, have their sails angled in the opposite direction in each hemisphere to catch the prevailing winds. However the direction in which the nudibranch egg coil is spiralled is the same throughout the world. One example I have illustrated above, Onchidoris depressa, is a good example as it is a north Atlantic species which has apparently arrived here in the southern hemisphere by hitching a ride on the bottom of a ship. If the position on the earth somehow affected the direction of spiralling you would expect it to change in Onchidoris but it doesn't. If anyone has photos of clockwise spiralling egg masses to prove me wrong please send them in.