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A new catalogue of 125 galactic SNRs is presented. A surface brightness-diameter relationship, corrected for variation in height I z I above the galactic plane, is derived and applied to the catalogue to yield I z I-corrected distances and diameters. A birth rate of about one every 30 or 40 years is indicated from the number-diameter diagram.

Parkes 2·7 and 5·0 GHz polarization maps have been combined to obtain distributions of magnetic field, Faraday rotation and depolarization for 20 supernova remnants.

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Observations of polarised radio emISSIOn from supernova remnants are reviewed and maps presented for the projected magnetic fields deduced from these observations. It is fairly clear that the fields in the young objects are radial and that there is a strong bias towards finding these objects in polarisation surveys. Well-defined tangential fields can be seen only in older remnants which are located well off the galactic plane.

Two examples are given of probable radio jet/supernova remnant associations: G332.4+0�1 and G 315 �8 - O� O. In both cases the jet length is larger than the radius of the remnant's shell, and the jet diameter is barely resolved and substantially less than the observed shell thickness. The jet luminosity is 5-10% that of the shell. The G332�4 +0.1 jet terminates 'in an extended plume whose luminosity is about 50% that of the shell.

Detailed 4.8 and 8.6 GHz radio images of the entire Large Magellanic Cloud with half-power beamwidths of 33 00 at 4.8 GHz and 20 00 at 8.6 GHz have been obtained using the Australia Telescope Compact Array. A total of 7085 mosaic positions were used to cover an area of 6 on a side. Full polarimetric observations were made. These images have sufficient spatial resolution ($8 and 5 pc, respectively) and sensitivity (3 of 1 mJy beam À1 ) to identify most of the individual supernova remnants and H ii regions and also, in combination with available data from the Parkes 64 m telescope, the structure of the smooth emission in that galaxy. In addition, limited data using the sixth antenna at 4.5-6 km baselines are available to distinguish bright point sources (<3 00 and 2 00 , respectively) and to help estimate sizes of individual sources smaller than the resolution of the full survey. The resulting database will be valuable for statistical studies and comparisons with X-ray, optical, and infrared surveys of the LMC with similar resolution.