  The filled skutterudite superconductor PrPt4Ge12 was studied in muon-spin
rotation (muSR), specific heat, and electrical resistivity experiments. The
continuous increase of the superfluid density with decreasing temperature and
the dependence of the magnetic penetration depth \lambda on the magnetic field
obtained by means of muSR, as well as the observation of a T^3 dependence of
the electronic specific heat establish the presence of point-like nodes in the
superconducting energy gap. The energy gap was found to be well described by
\Delta =\Delta_0| k_x - ik_y| or \Delta = \Delta_0(1 - k_y^4) functional forms,
similar to that obtained for another skutterudite superconductor, PrOs4Sb12.
The gap to T_c ratios were estimated to be \Delta_0/k_BT_c = 2.68(5) and
2.29(5), respectively.
