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The most intense hard x -ray source in the confused region in Scorpius has been identified as 4U1700-37 ( =HD153919). Observations extending over three binary periods in 1978 September were carried out with the high energy x-ray spectrometer on OSO-8. The 3.4-day modulation is seen above 20 keV with the intensity during eclipse being consistent with zero flux. The photonnumber spectrum from 20 to 150 keV is well represented by a single power law with a photonnumber spectral index of —2.77 ± 0.35 or by a thermal bremsstrahlung spectrum with kT = 27 (+15,-7) keV. The counting rate above 20 keV outside of eclipse shows no evidence for the 96.8-min x -ray modulation previously reported at lower energies. Despite the difficulties that exist in reconciling both the lack of periodic modulation in the emitted x-radiation and the orbital dynamics of the system with our currently accepted theories of the evolution and physical properties of neutron stars, the observed properties of 4U 1700-37 are all consistent with the source being a spherically accreting neutron star rather than a black hole.