418 



stimulation of tlie auricle, an extra-ventricle-systole is brought about. 

 We see now the T-oseillation after extra-stimulation of the basis 

 ventriculi about as large as after extra-stimulation of the auricle. 

 The anticipated ventricle-systole is brought about in the latter case 

 by the "Erregung" that reaches the ventricle along the usual con- 

 nection-sys.tems. The epoch of the ventricle at which the anticipated 

 ventricle-systole begins, and not the place where the stimulus attacks, 

 determines the extent of the T-oscillations. It is obvious that this 

 does not hold, when an extra-stiniulation hits the point. Hut here 

 the T-oscillaiion of the ventricle-systole varies the more intensively 

 in a positive sense, in proportion as the extra-stimulus reaches the 

 ventricle at an earlier e|)0ch of the ventricle-period. This is distinctly 

 to be seen in Fig. 10. At 1 and 3 the extra-stimulaiion reaches the 

 ventricle-point at an early epoch of the ventricle-period. Now very 

 large positive T-oscillations set in. At 2 the extra-stimulation hits 

 the ventricle-point at a later epoch. Consequently the positive T is 

 now smaller. If at 4 the ventricle-point is hit by the extra-stimulation 

 at a still later epoch, the positive T is again still considerably 

 smaller. At 4 the basis-negativity had already begun, when the 

 extra-stimulation set in, and brought the string back to and beyond 

 the 0-position. It appears consequently that the ventricle-point is 

 irritable in the ascending line of the R-oscillation. 



The basis-negativity is consequently so much the more intensive 

 in the ventricle-electrograms of the extra-systoles after extra-stimul- 

 ation at the end of these electrograms, in proportion as the extra- 

 stimulation hits the ventricle-point at an earlier epoch of the 

 ventricle-period. 



