Fig. 9. Logarithm of the X-ray luminosity as a function of the J magnitude, both corrected for extinction (see CMFA for details), using X-ray sources in the Monoceros cloud for which this correction can be made (Table 5). The data are compared to the correlation obtained for the Oph core members (CMFA), 1 standard deviation (dashed lines). The comparison suggests that the X-ray source population in Monoceros and Oph are very similar.