1. The behaviour of the male culminating in spermatophore formation is divisible into four phases: approach; mounting; copulation; and spermatophore formation. All appear to be controlled and co-ordinated solely through the nervous system.
2. The initiation of sexual behaviour requires the brain and one or more of the receptor-bearing head structures (antennae, palpi and eyes) to be functional.
3. Approach and mounting behaviour involves the receptors, nervous system and effectors of the head and thorax only.
4. Copulation is controlled through the ganglia of the abdomen but for its initiation these ganglia have to be in nervous communication with a centre anterior to them. Also both cerci must be functional.
5. Spermatophore formation is initiated, and its early stages are controlled, by an anterior centre which has its effect through the last abdominal ganglion. The later stages of formation appear to be controlled by the last abdominal ganglion alone.
6. The presence of the female is essential for the initiation and early stages of spermatophore formation, but her role during the later stages of the process appears to be a completely passive one.