The suitability of Gaussian distribution functions to describe the shape and temperature dependence of the UV absorption continua of peroxy radicals has been investigated. The ethylperoxy radical was used as a test case. Its 298 K absorption continuum was found to be best described by a semilogarithmic Gaussian distribution function. A linear Gaussian distribution function performed less well but still adequately described the continuous absorption. The temperature dependence of the ethylperoxy radical UV absorption continuum was also well predicted. Analogous results obtained for the methylperoxy radical support these conclusions. A theoretical comparison of the semilogarithmic and linear Gaussian distribution functions is given and a potential energy diagram of the ethylperoxy radical derived. The experimentally determined absorption cross sections of HO2. have been reanalyzed. It is shown that either the measurements at short wavelengths are in error or an unidentified electronic transition of HO2. exists.