  As found by Bordemann and Hoppe and by Jevicki, a certain non-relativistic
model of an irrotational and isentropic fluid, related to membranes and to
partons, admits a Poincar\'e symmetry. Bazeia and Jackiw associate this
dynamical symmetry to a novel type of ``field dependent'' action on space-time.
The ``Kaluza-Klein type'' framework of Duval et al. is used to explain the
origin of these symmetries and to derive the associated conserved quantities.
In the non-interacting case, the symmetry extends to the entire conformal
group.
