  An analysis of the candidate embedded stellar systems in the reflection
nebulae vdBH-RN26, vdBH-RN38, vdBH-RN53a, GGD20, ESO95-RN18 and NGC6595 is
presented. Optical spectroscopic data from CASLEO (Argentina) in conjunction
with near infrared photometry from the 2MASS Point Source Catalogue were
employed. The analysis is based on source surface density, colour-colour and
colour-magnitude diagrams together with theoretical pre-main sequence
isochrones. We take into account the field population affecting the analysis by
carrying out a statistical subtraction. The fundamental parameters for the
stellar systems were derived. The resulting ages are in the range 1-4 Myr and
the objects are dominated by pre-main sequence stars. The observed masses
locked in the clusters are less than 25 solar masses. The studied systems have
no stars of spectral types earlier than B, indicating that star clusters do not
necessarily evolve through an HII region phase. The relatively small locked
mass combined with the fact that they are not numerous in catalogues suggests
that these low mass clusters are not important donors of stars to the field
populations.
