Parkes full polarization spectra of OH masers - II. Galactic longitudes
  240 to 350
  Full polarization measurements of 1665 and 1667-MHz OH masers at 261 sites of
massive star formation have been made with the Parkes radio telescope. Here we
present the resulting spectra for 157 southern sources, complementing our
previously published 104 northerly sources. For most sites, these are the first
measurements of linear polarization, with good spectral resolution and complete
velocity coverage.
  Our spectra exhibit the well-known predominance of highly circularly
polarized features, interpreted as $\sigma$ components of Zeeman patterns.
Focusing on the generally weaker and rarer linear polarization, we found three
examples of likely full Zeeman triplets (a linearly polarized $\pi$ component,
straddled in velocity by $\sigma$ components), adding to the solitary example
previously reported. We also identify 40 examples of likely isolated $\pi$
components, contradicting past beliefs that $\pi$ components might be extremely
rare. These were recognised at 20 sites where a feature with high linear
polarization on one transition is accompanied on the other transition by a
matching feature, at the same velocity and also with significant linear
polarization.
  Large velocity ranges are rare, but we find eight exceeding 25 km/s, some of
them indicating high velocity blue-shifted outflows. Variability was
investigated on timescales of one year and over several decades. More than 20
sites (of 200) show high variability (intensity changes by factors of four or
more) in some prominent features. Highly stable sites are extremely rare.
