The 6-GHz methanol multibeam maser catalogue - IV. Galactic longitudes 186°-330° including the Orion-Monoceros region

We present the fourth portion of a Galactic plane survey of methanol masers at 6668 MHz, spanning the longitude range 186 degrees 330 degrees. We report 207 maser detections, 89 new to the survey. This completes the southern sky part of the methanol multibeam survey and includes a large proportion of new sources, 43 per cent. We also include results from blind observations of the OrionMonoceros star-forming region, formally outside the latitude range of the methanol multibeam survey; only the four previously known methanol emitting sites were detected, of which we present new positions and spectra for masers at Orion A (south) and Orion B, obtained with the Multi-Element Radio Linked Interferometer Network (MERLIN) array.