IRAC 2 (left) and IRAC 4 (right) maps with same source markers as Fig. 1. These maps can give a sense for sources where continuum emission correspond to a clear and isolated source as seen with Spitzer, or where some confusion with nearby sources is possible. Note that YSO identifications and classifications by D15 following the c2d method required detections in all four IRAC bands (3.6, 4.5, 5.8 and 8.0 μm) and the MIPS 24 μm band.