Proton intensities and energy spectrums in the inner Van Allen belt have been measured with shielded plastic scintillators on three satellites and an Atlas pod. Omnidirectional fluxes of protons above 59, 95, and 148 Mev are given at the equator forLvalues of 1.25 and 1.48–1.60, and isoflux contours are given inB,Lspace for protons above 59 Mev. The counting rates of three scintillation counters having threshold energies of 46, 76, and 128 Mev have been analyzed in terms of assumed energy spectrums of the formdф/dE=AE−nanddф/dE=Ae−E/E0. The second form produces a dependence on the geomagnetic parameterLgiven byE0= 460L−4.8Mev. For the theoretical spectral shapes of Lenchek and Singer, cutoff energies have been derived from the ratios of counting rates in the three detectors. The results are in moderately good agreement with the calculations of Singer (in which, because of nonadiabatic effects, the cutoff momentum was found to be of the formPmax=POL−2), with a best fit valuePO=