  We have extended our analytical chemical evolution modelling ideas for the
Galaxy to the Magellanic Clouds. Unlike previous authors, we assume neither a
steepened IMF nor selective galactic winds, since among the alpha-particle
elements only oxygen shows a large deficit relative to iron and a similar
deficit is also found in Galactic supergiants. Thus we assume yields and time
delays identical to those we previously assumed for the solar neighbourhood. We
include inflow and non-selective galactic winds and consider both smooth and
bursting star formation rates, the latter giving a better fit to the
age-metallicity relations. We predict essentially solar abundance ratios for
primary elements and these seem to fit most of the data within their
substantial scatter. Our LMC model also gives a remarkably good fit to the
anomalous Galactic halo stars discovered by Nissen & Schuster (1997).
  Our models predict current ratios of SNIa to core-collapse supernova rates
enhanced by 50 per cent and 25 per cent respectively relative to the solar
neighbourhood, in fair agreement with ratios found by Cappellaro et al. (1993)
for Sdm-Im relative to Sbc galaxies, but these ratios are sensitive to detailed
assumptions about the bursts. We consider that the high SNIa/SNII ratios found
in some late-type galaxies are related to their star formation history rather
than to any differences in the IMF.
