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Catalogues are presented of radio supernova remnants in both Large (LMC) and Small (SMC) Magellanic Clouds together with maps of the LMC remnants prepared at a frequency of 843 MHz and with a resolution of 43 x 45 arcsec. The 38 confirmed remnants are believed to represent a reasonably complete sample for diameters less than about 40 pc although the LMC catalogue is probably very incomplete for larger diameters. The supernova remnants (SNRs) are compared with the Galactic remnants in the catalogue of Clark and Caswell (1976) and they are found to be similar in many ways. In particular a distance scale derived from the Cloud SNRs reproduces well the mean distances of directly measured Galactic calibrators. The usual model of a SNR expanding adiabatically from a small diameter is not supported by the statistics of the numberdiameter relation which suggest that rapid expansion up to quite large diameters is common. The physical implications are discussed. A supernova rate of about four per century is derived for the Galaxy and about one per century for the two Magellanic Clouds combined.

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SummaryA method of constructing an aerial system of high resolution but small area and low cost is described. Its application to the production of narrow pencil beams at metre wavelengths for investigations in radio astronomy is discussed. A small-scale model has been constructed to test the principle.

The fourth catalogue of radio sources observed at 408 MHz with the Molonglo radiotelescope is presented. A total of 1349 sources is listed to a limiting flux density of 0�2 Jy, the catalogue being largely complete above 0� 25 Jy. The area of sky surveyed includes the Magellanic Clouds as well as a comparison region of similar angular extent. Detailed notes are provided on some of the Cloud sources, and maps are given for complex sources in the region of the Clouds. Those sources for which high-frequency or optical data are available are classified into two lists, one of Cloud members and the other of 'unidentified nonthermal sources', presumably not Cloud members.