Abstract: Apparatus for analyzing particles in which the particles traverse a sensing zone one at a time. A first detector measures variations in the conductivity of the fluid caused by the presence of a particle in the sensing zone. A laser irradiates the sensing zone and a second detector is provided responsive to light scattered by particles in the sensing zone. Additional detectors are provided responsive to fluorescence from the particles. The signals from each of the detector means are digitized and stored and then compared. The differences in successive waveforms from each detector indicate the presence of abnormal particles. Waveform shape is also used as an indication of the shape of the particles.