34 CORA SENNER WINKIN 



identical to that in intact animals: ether was reduced, a corneal reflex 

 elicited, and successive occlusion of the arteries done as soon as recovery 

 from the last preceding occlusion had occurred. The cats differed 

 somewhat in the rapidity with which the effect of the ligation of the 

 adrenals appeared in the anemic blood pressure curve. In two 

 cats, 52 and 56, the first occlusion following ligation showed little 

 difference, and certainly no curtailment when compared with the 

 control curve. In cat 52 the level of maximal pressure was maintained 

 2 full minutes longer than in the control. However, in the other four 

 cats, the curves obtained following ligation of the glands immediately 

 presented a marked contrast as compared with the normal occlusion 

 and with the records obtained under repeated occlusion in the control 

 series of intact animals. The characteristic feature of this change 

 appeared at once and was retained until failure of the animal. This 

 was an absolute halving of the occlusion time, and the retention, either 

 of a reduced double curve, or of a single vigorous rise. In the two cats, 

 52 and 56 already referred to, this same reduction appeared somewhat 

 later in the record. The occlusion time was not halved in cat 52 until 

 the fifth occlusion following ligation of the glands; in cat 56, not until 

 the fourth occlusion. In both these cats there also remained a dis- 

 tinct double rise in the pressure curve, which was not observable in 

 the curves from the other animals. Autopsy showed no difference 

 in the completeness of the ligation in these two animals. 



In the cats in which the adrenals had been ligated the complete in- 

 ability to restore the bulbar functions had to be faced in all cases before 

 nine successive occlusions had been made. There were no exceptions 

 to this early complete collapse in any of the cats observed. Two cats, 

 54 and 52 already mentioned, gave eight successive occlusions after 

 ligation of the glands. Cat 53 gave seven; (fig. 5 C) cat 57, five; cat 

 56, otherwise so resistant to a change in its long occlusion periods and 

 retention of normal contour, succumbed after only four occlusions. 

 Only one occlusion was obtained from cat 55. Figured in hours of 

 survival under this procedure, this meant a maximal survival of 2^ 

 hours, a minimal survival of 15 minutes. However, only two cats of 

 the series failed within an hour of the ligation of the glands under suc- 

 cessive occlusions. The average survival time was 1| hours. 



Very few indications of the approaching collapse appeared in the 

 record, the only index being perhaps the very low level of blood pres- 

 sure between any two successive occlusions. This low level was estab- 

 lished in all cases immediately after the spontaneous fall of pressure 



