UPON THE VASCULAR SYSTEM. 127 



Experiment XXVI. — Strong full-grown rabbit. Fed two hours before the 

 experiment. The cavity of the stomach was not opened. When the superior 

 cardiac branches'* of the vagi were divided, no evident change resulted in the 

 vascularity of the stomach or intestines. On dividing the vagi the ivhole outer 

 surface of the stomach became paler ; but no such change was observed in the 

 mesentery or intestines. The vascular change in the stomach was permanent. 



The upper ends of both vagi were then repeatedly stimulated, with variable 

 results. Sometimes the surface of the stomach became paler, at other times 

 redder. Irritation of the lower ends of the nerves produced no effect. 



Experiment XXVII. — Rabbit ; fed an hour before the vagi were divided. 

 The outer surface of the stomach was not apparently so vascular as in the three 

 former cases. Division of the vagi produced no evident change on the gastric 

 vessels. 



Experiment XXVIII. — A cat fed on milk an hour previous to division of 

 the vagi. On section of these nerves the vascularity of the outer surface of the 

 stomach instantly became greatly diminished, and remained so. 



(b.) Section of the Vagi during Fasting. 



Experiment XXIX. — Full-grown rabbit which had fasted for twelve hours. 

 Outer surface of stomach pale. Division of depressor nerves produced no 

 evident change in gastric or intestinal vessels. Division of both vagi likewise 

 produced no evident change in gastric or intestinal vessels. Irritation of upper 

 end of right vagus (1 Smee, secondary 200 mm. distant from primary coil) 

 caused slight reddening of outer surface of stomach, no change on intestinal 

 vascularity. This observation was repeated with a stronger current (secondary 

 coil at 150). A slight increase in the pallor of the stomach was the immediate 

 result, but this yielded during the continuance of the irritation to distinct red- 

 dening of the gastric wall. The irritation was continued for twenty seconds. 

 Anaesthesia was then produced by means of chloroform in order to get rid of 

 the effects of the irritant upon the sensory nerve centres. The upper end of 

 the right vagus was then stimulated (secondary coil at 100). Slight but distinct 

 increase in the gastric vascularity at once ensued. Irritation of the upper end 

 of the left nerve yielded the same result. Irritation of the lower ends of the 

 nerves caused no change. 



Experiment XXX. — Full-grown rabbit which had fasted for fourteen hours. 

 Division of the nervi depressores and vagi produced no evident change on the 

 vascularity of the outer wall of the stomach or of the intestines, which both 

 before and after the division were but slightly vascular. 



* These nerves produce dilatation of abdominal blood-vessels. 

 VOL. XXVI. PART I. 2 L 



