  We have used an antenna temperature thresholding algorithm on the Bell
Laboratories 13CO Milky Way Survey to create a catalog of 1,400 molecular
clouds. Of these, 281 clouds were selected for having well-determined kinematic
distances. The scaleheight, luminosity, internal velocity dispersion, and size
of the cloud sample are analyzed to show that clouds smaller than ~200,000
solar masses have a scaleheight which is about 35 pc, roughly independent of
cloud mass, while larger clouds, the Giant Molecular Clouds, have a reduced
scaleheight which declines with increasing cloud mass.
