Recent BIMA observations of extragalactic molecular clouds open new
avenues for studying the formation of Giant Molecular Clouds (GMCs).  I
will discuss the results of the BIMA campaign to map the star forming disk
of M33 in CO(J=1->0) which has provided the first flux-limited catalog of
Giant Molecular Clouds in any spiral galaxy.  The observations find 148
GMCs with masses as large as 7.5 X 10^5 M_sun.  The GMCs follow a
power-law mass spectrum with a surprisingly steep index of -2.6 +/- 0.2.
Despite this departure from the Milky Way value of -1.6, the clouds follow
power-law relations among their size, line width and mass with indices
indistinguishable from the values found in the Milky Way (Larson's Laws).

Since extragalactic observations do not suffer the line of sight blending
effects and distance ambiguities that plague observations of Milky Way
GMCs, the study of M33 makes an ideal data set to compare the distribution
of molecular gas with other "guilty parties" in the star forming process
(e.g. atomic gas, HII regions and OB associations).  GMCs are found
exclusively on high column density filaments of HI, strongly suggesting
the formation of molecular clouds directly from atomic gas.  Using the
mass and velocity of the atomic gas, the angular momentum for a forming
molecular cloud is found to be an order of magnitude larger than is
observed in the study.  I will discuss the implications of these results
for current theories of molecular cloud formation.

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