Phosphorus clusters containing up to 35 atoms are generated by laser ablation of red phosphorus using a XeCl laser (308 nm). The cluster cations ate identified by time-of-flight mass spectrometry. It is found that for an odd number of phosphorus atoms, bare cluster cations are preferentially produced, whereas for even number phosphorus atom clusters the cluster cations with an odd number of hydrogens (present in a trace amount in the source) are easily produced. The structural details of those clusters abundant in the laser ablation mass spectrum are discussed with the aid of theoretical (ab initio) model calculations.