  We present the first catalog of 67 strong galaxy-galaxy lens candidates
discovered in the 1.64 square degree Hubble Space Telescope COSMOS survey.
Twenty of these systems display multiple images or strongly curved large arcs.
Our initial search is performed by visual inspection of the data and is
restricted, for practical considerations, to massive early-type lens galaxies
with arcs found at radii smaller than ~5''. Simple mass models are constructed
for the best lens candidates and our results are compared to the strong lensing
catalogs of the SLACS survey and the CASTLES database. These new strong
galaxy-galaxy lensing systems constitute a valuable sample to study the mass
distribution of early-type galaxies and their associated dark matter halos. We
further expect this sample to play an important role in the testing of software
algorithms designed to automatically search for strong gravitational lenses.
  From our analysis a robust lower limit is derived for the expected occurrence
of strong galaxy-galaxy systems in current and future space-based wide-field
imaging surveys. We expect that such surveys should uncover a large number of
strong lensing systems (more than 10 systems per square degree), which will
allow for a detailed statistical analysis of galaxy properties and will likely
lead to constraints on models of gravitational structure formation and
cosmology. The sample of strong lenses is available here:
http://cosmosstronglensing.uni-hd.de/
