A theory of tracheal respiration in insects

Abstract

Abstract A satisfactory theory of tracheal respiration would not only be of considerable academic interest but, since respiratory poisons are employed for the destruction of many harmful insects, it might prove of great practical value. Physiological studies on the tracheæ of insects have aimed chiefly at establishing, on the one hand, the mode of ending of these air-containing tubes, and, on the other, the forces which maintain the supply of oxygen to their terminations. As regards the former of these problems, there is no general agreement; for most of those who have studied the subject have worked with different organs from different insects, and almost all have assumed that the farthest point to which they have succeeded in tracing the tubes is in fact their termination. In certain cases, however, there is no doubt that the tracheal capillaries or tracheoles penetrate within the cytoplasm of the tissue cells (see Wigglesworth, 1929).