[Sequence of the spread of excitation in bird heart ventricles].

Intramural multipolar technique revealed primary sites of excitation in the subendocardium of central areas of border line of the apical and middle thirds of the bird heart septum. From the zone of primary depolarization the excitation wave spread on the subendocardium of ventricles. A number of sites of negativity were observed over the epicardium. The main mass of myocardium of free walls and the lower two thirds of the septum are activated by means of myocardium of free walls and the lower two thirds of the septum are activated by means of multifocal depolarization. The base third of the septum is the last to be activated. These features of the excitation of bird myocardium can be accounted for by the special character of distribution of the Purkinje fibers in the muscles of myocardium ventricles.