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Observations with the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Observatory show more than 30 unidentified sources of E$>$100 MeV gamma rays concentrated along the galactic plane (Fichtel et al., 1994, ApJS, in press). Based on their spatial distribution, their typical distances are 2-6 kpc. Combining these distances with the observed gamma-ray fluxes gives luminosities above 100 MeV in the range (0.1 - 1) x 10$^{36}$ ergs/s. These derived luminosities are higher than those of most of the observed gamma-ray pulsars, even when substantial beaming is considered. It is unlikely, therefore, that most of these sources closely resemble Geminga, which is an older, nearby pulsar with a total spin-down luminosity $\dot E$ of only 3 x 10$^{34}$ ergs/s and an approximate gamma-ray luminosity of 2 x 10$^{33}$ ergs/s for an assumed distance of 250 pc. If these sources are undiscovered pulsars, they are probably younger and more distant, with the principal simil! arity to Geminga being that they h ave no observable radio pulse. For most of these, finding an unknown short-period pulsation with the gamma-ray data alone will be extremely difficult.
