TRANK MORRELL 



377 



Fig. 2 

 Characteristics of the dependent niirnir focus, hi the ink-written tracing the upper 

 two channels record the primary focus and the lower two channels the mirror 

 focus. The ethyl chloride lesion is indicated by cross hatching. Calibration: lOO 

 microvolts and i second. In the oscillographic tracing the upper channel records the 

 primary region and the lower one the secondary region. Calibration: loo msec. 



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Fig. 3 

 Electrographic characteristics of tlie independent mirror focus. Electroencephalogram of an 

 unanaesthetized rabbit taken 3 weeks after production of an ethyl chloride lesion in the area 

 designated by cross hatching. Discharges originating in the primary lesion (electrode 2) and 

 in the secondary region (electrode 7) are unrelated in time of occurrence. Note also that there 

 is some depression of activity in electrodes just posterior to the primary lesion while this is not 

 true of electrodes posterior to the mirror focus. Calibration: 50 microvolts and i second. 



