  We study the current-driven motion of metastable localized spin structures
with various topological charges in a (Pt$_{1-x}$Ir$_{x}$)/Fe bilayer on a
Pd(111) surface by combining atomistic spin model simulations with an approach
based on the generalized Thiele equation. We demonstrate that besides a
distinct dependence on the topological charge itself the dynamic response of
skyrmionic structures with topological charges $\mathrm{Q} = -1$ and
$\mathrm{Q}= 3$ to a spin-polarized current exhibits an orientation dependence.
We further show that such an orientation dependence can be induced by applying
an in-plane external field, possibly opening up a new pathway to the
manipulation of skyrmion dynamics.
