In a previous article, Hansen et al. (see Phys. Rev. lett., vol.69, p.652 (1992) and ibid., vol.98, p.4128 (1993)) presented a molecular dynamics (MD) simulation study of the melting of butane and hexane monolayers on graphite. Their extensive simulations show that the mechanisms for the melting transitions of these monolayers are different in nature: molecular flexibility reflected by the formation of gauche defects is important for hexane, whereas butane molecules undergo tilting prior to the phase transition. These two mechanisms allow for the molecules to disorder both rotationally and translationally In addition, they determined the melting temperatures of the monolayers, which were at odds with experiment by 25% to 30% in both cases, The purpose of the present note is to elucidate the discrepancy between simulation and experiment as regards the location of the melting transition ill a hexane monolayer, and to address the influence of both surface potential strength and intermolecular interactions on the transition.