ELECTRONIC COUNTING OF ELONGATED PARTICLES IN SUSPENSION.

A counting instrument is proposed that could count elongated particles, such as nematodes, individually in the presence of a suspension of differently shaped particles the sensor of the device would have detector probes spaced along a tunnel through which the rod-like particles would pass. In the conductivity detector, the nematode passing between opposing electrodes in the tunnel interrupts the normal current through the electrolyte, effecting the indicator pulse. The detectors are spaced ac cording to nematode length so that the same nematode will produce a pulse at each detector the coincident pulses are modified electronically so that pulse height and width can be used to distinguish a nematode from associated debris.