A silicon target enriched in 29Si has been bombarded with 9 MeV3He++ particles, and the emitted protons have been observed with a magnetic spectrometer. A silicon target enriched in 30Si has been bombarded with 10 MeV3He++ particles, and the emitted deuterons have also been observed with a magnetic spectrometer. The excitation energies of 45 levels in 31P have been determined and the results are compared with previous results. © 1969.