Short wavelength fluctuations may be a source of anomalous transport in toroidal plasmas. Early investigations concerned electron and ion modes that occur only at a particular radius and have a localised eigenfunction: such modes do not seem important for transport. Recently, Connor, Taylor and Wilson [1] described electron modes that occur at all radii and have extended eigenfunctions: these could lead to large transport. Similar ion modes were described by Romanelli and Zonca [2]. All these modes have discrete frequency spectra. Now, Kim and Wakatani [3] have described electron modes that occur at all radii but are localised and, it is claimed, have a continuous spectrum. We re-examine this problem of mode structure and location. We find that there are just two basic forms: 'isolated' modes that occur only at a particular radius and 'general' modes that occur at all radii. Isolated modes are always localised. In special circumstances general modes may be extended, but in typical cases they are also localised. All modes have a discrete spectrum. These results are consistent with a diffusion coefficient having the Bohm scaling and decreasing with plasma rotational velocity shear.