  We compare the stellar wind features in far-UV spectra of Sk -67 111, an O7
Ib(f) star in the LMC, with Sk 80, an O7 Iaf+ star in the SMC. The most
striking differences are that Sk 80 has a substantially lower terminal
velocity, much weaker O VI absorption, and stronger S IV emission. We have used
line-blanketed, hydrodynamic, non-LTE atmospheric models to explore the origin
of these differences. The far-UV spectra require systematically lower stellar
temperatures than previous determinations for O7 supergiants derived from
plane-parallel, hydrostatic models of photospheric line profiles. At these
temperatures, the O VI in Sk -67 111 must be due primarily to shocks in the
wind.
