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We present a study of the inclusive production of neutral pions and charged particles from 112 000 hadronic Z° decays. The measured inclusive momentum distributions can be reproduced by parion shower Monte Carlo programs and also by an analytical QCD calculation. Comparing our results to e+e" data between ^= 9 and 91 GeV, we find that the evolution of the spectra with center of mass energy is consistent with the QCD predictions.

We search for new resonances, Y, with mass, My, in the range from 30 to 89 GeV, produced via the reaction e+e-,Z°-,),Y, where Y subsequently decays into e + e-, IX +Ix-or hadrons. We use 5.5. pb-1 of data collected in the energy range 88.2 ~ x/~ ~< 94.2 GeV, near the Z ° peak. We obtain the following upper limits, at the 95% confidence level, on the product of the branching ratios: BR(Z°-,~/Y)XBR(Y-.e+e-)<2.8×10-4 for 30

We have searched for direct leptoquark production in Z ° decays from a scan of the Z ° resonance, in the energy range 88.2 ~< x/] ~< 94.2 GeV, using 5.2 pb-~ of data. We exclude the existence of scalar leptoquarks with masses less than 41 to 44 GeV, depending on the charge assignments, at the 95% confidence level.