A trap for flying insects that incorporates some of the principles described by Williams and Milne (1935) and Chamberlin and Lawson (1910) was constructed. It consists basically of two conical nets that rotate in a horizontal plane around a central axis that is driven by an electric motor through a series of pulleys. The efficiency of the trap is not affected by wind as an increased airflow through one net is balanced by a decreased airflow through the other. It is green in colour to blend with its surroundings. The trap (Fig. 1) is 5½ feet high at the centre. It has three main sections (Fig. 2): the framework, the drivillg mechanism, and the nets.