We re-examine the recent suggestion of a high fraction of transition discs ( i.e .
those with a cleared inner hole ) in M stars , motivated by the fact that we expect that , for M stars , even discs without inner holes should exhibit very weak excess shortward of around 10 \mu m. Our analysis of spectral energy distribution models suggest that this indeed means that M stars where a detectable excess begins at around 6 \mu m may be mis-classified as transition discs when in fact they have optically thick dust extending in to the dust sublimation radius .
Consequently , we estimate that the transition disc fraction among M stars in the Coronet cluster is \sim 15 \pm 10 \% ( rather than the recently claimed value of 50 \% ) .
This revised figure would imply that the transition disc fraction is not after all markedly higher in later type stars .
We suggest that for M stars , transition discs can only be readily identified if they have emission that is close to photospheric out to > 10 \mu m .