We investigate the time-evolutions of angular distributions for
$B_s$ decays into final states that are admixtures of CP-even
and CP-odd configurations. A sizable lifetime difference between
the $B_s$ mass eigenstates allows a probe of CP violation in
time-dependent untagged angular distributions. Interference effects
between different final state configurations of $B_s\rightarrow D^{*+}_s\,
D^{*-}_s$, $J/\psi\,\phi$ determine the Wolfenstein parameter $\eta$
from {\it untagged} data samples, or – if one uses $|V_{ub}|/|V_{cb}|$
as an additional input – the notoriously difficult to measure CKM
angle $\gamma$. Another determination of $\gamma$ is possible by
using isospin symmetry of strong interactions to relate {\it untagged}
data samples of $B_s\to K^{\ast+}\,K^{\ast-}$ and $B_s\to K^{\ast0}\,
\overline{K^{\ast0}}$. We note that the {\it untagged} angular
distribution for $B_s\to\rho^0\phi$ provides interesting information
about electroweak penguins.
