  The Cygnus-X star-forming complex is one of the most active regions of low
and high mass star formation within 2 kpc of the Sun. Using mid-infrared
photometry from the IRAC and MIPS Spitzer Cygnus-X Legacy Survey, we have
identified over 1800 protostar candidates. We compare the protostellar
luminosity functions of two regions within Cygnus-X: CygX-South and CygX-North.
These two clouds show distinctly different morphologies suggestive of
dissimilar star-forming environments. We find the luminosity functions of these
two regions are statistically different. Furthermore, we compare the luminosity
functions of protostars found in regions of high and low stellar density within
Cygnus-X and find that the luminosity function in regions of high stellar
density is biased to higher luminosities. In total, these observations provide
further evidence that the luminosities of protostars depend on their natal
environment. We discuss the implications this dependence has for the star
formation process.
