  We present the results of an AAT wide-field camera survey of the stars in the
Monoceros Ring and purported Canis Major overdensity in the Galactic longitudes
of {\it l} = (193 - 276)$^\circ$. Current numerical simulations suggest that
both of these structures are the result of a single on-going accretion event,
although an alternative solution is that the warped and flared disc of the
Galaxy can explain the origin of both of these structures. Our results show
that, with regards the Monoceros Ring, the warped and flared disc is unable to
reproduce the locations and strengths of the detections observed around the
Galaxy. This supports a non-Galactic origin for this structure. We report 8 new
detections and 2 tentative detections of the Monoceros Ring in this survey. The
exact nature of the Canis Major overdensity is still unresolved although this
survey provides evidence that invoking the Galactic warp is not a sufficient
solution when compared with observation. Several fields in this survey are
highly inconsistent with the current Galactic disc models that include a warp
and flare, to such an extent that explaining their origins with these
structures is problematic. (Abridged)
