30′ × 30′ RGB images (with R = [ 8.0 ], G = [ 4.5 ], B = [ 3.6 ]) from the GLIMPSE survey showing regions around Mercer 20 (left) and Mercer 70 (right), which are inside the white circles of radius 1′. Blue circles are young stellar objects or candidates (double circles: with available distance measurement); green squares poinpoint Extended Green Objects; and yellow crosses are masers. In order to preserve the observational homogeneity in this figure, new YSO candidate detections by Dirienzo et al. (2012) have been excluded from the left panel (see text for details). North is up and east is left.