  We measure the angular correlation function, w(theta), from 0.5 to 30
arcminutes of detected sources in two wide fields of the Herschel Multi-tiered
Extragalactic Survey (HerMES). Our measurements are consistent with the
expected clustering shape from a population of sources that trace the dark
matter density field, including non-linear clustering at arcminute angular
scales arising from multiple sources that occupy the same dark matter halos. By
making use of the halo model to connect the spatial clustering of sources to
the dark matter halo distribution, we estimate source bias and halo occupation
number for dusty sub-mm galaxies at z ~ 2. We find that sub-mm galaxies with
250 micron flux densities above 30 mJy reside in dark matter halos with mass
above (5\pm4) x 10^12 M_sun, while (14\pm8)% of such sources appear as
satellites in more massive halos.
