Physiology of locomotion of the Blatta orientalis L. II. Importance of legs in the nerve coordination in walking

Abstract

The importance of the mechanical and nervous factors depending on the legs with regard to the nervous coordination of locomotion, is studied in the cockroach Blatta orientalis.

Amputation was made at different apendix levels; anaesthesla by injection of cocaine chlorhydrate in the femur; flxing with pitch, and curare injection in the coxal region.

Amputation, anaesthesla, flxing and curare injection of one leg does not modify in any way movement coordination of the remaining legs for locomotion of the Blatta.

The same procedures, on affecting any two legs of different sido, provoke the appearance of a new type of coordination for the progress with the four remaining legs; the animal moves the legs opposed crosswise, synchronically in running and with scarce interval on advancing slowly, completely independent of coordination in the normal animal.

In order to modlfy the coordination by amputation of two legs, the section has to be carried out at levels near the femur, cióse to the coxal.

Taking into account the analogy of the results by the different procedures above named, the factors whlch may influence conditioning the different type» of coordi­nation are discussed. It is concluded that the most important factors must be the Peripherie impulses reaching the thcracic ganglions starting from kinetic receptora.