VASOMOTOR REFLEXES 



367 



Our experiments also have led to the conclusion that there is 

 no essential qualitative difference between the various nerves 

 subjected to stimulation (sciatic, tibial, peroneal, median, ulnar). 

 A possible exception may be made in the case of the saphenous. 

 It may be that there is a greater tendency to a fall on stimu- 

 lating this nerve than in the case of others. Whatever the nerve 

 may be, whether a purely sensory nerve, as the saphenous; a 

 mixed nerve, as the sciatic, peroneal, tibial, ulnar, or median, 

 or a purely motor nerve, such as a muscular branch of the fe- 

 moral, the course of response to weak and strong stimulation was 

 in most cases a fall and a rise as already described in section 3. 



A few examples are quoted in tabular form where a selected 

 purely sensory nerve and a purely motor or a mixed nerve ap- 

 parently of the same size were stimulated in turn under entirely 

 similar conditions. 



Sensory and motor nerves compared 



ARRANGEMENTS OF STIMULATION 



1 battery coil at 30 cm. 15 seconds. 

 1 battery coil at 25 cm. 15 seconds. 

 1 battery coil at 20 cm. 15 seconds. 

 1 battery coil at 15 cm. 15 seconds. 

 1 battery coil at 10 cm. 15 seconds. 

 1 battery coil at 5 cm. 15 seconds . 

 1 battery coil at cm. 15 seconds, 



RIGHT SAPHENOUS 



—4 mm. Hg. 



— 10 mm. Hg. 



-10, +2 mm. Hg. 



+4, -12 mm. Hg. 



+6, —14 mm. Hg. 

 +16, -18 mm. Hg. 

 +22, -14 mm. Hg. 



BRANCH OP RIGHT 

 FEMORALIS 



0, mm. Hg. 



-1, +2 mm. Hg. 



-4, +2 mm. Hg, 



+4, mm. Hg. 



+8, -2 mm. Hg. 



+ 14, -12 mm. Hg. 



+26, -14 mm. Hg. 



(From experiment 47. Under brain compression.) 



The sign ' — ' means a pure fall of blood-pressure, '+' a pure rise, and ' — , +' 

 or ' + , — ' a mixed response, namely, a fall followed by a rise or a rise followed 

 by a fall, respectively. 



Sensory and mixed nerves compared 



ARRANGEMENTS OF STIMULATION 



1 battery coil at 30 cm. 15 seconds. 

 1 battery coil at 25 cm. 15 seconds. 

 1 battery coil at 20 cm. 15 seconds. 

 1 battery coil at 15 cm. 15 seconds . 

 1 battery coil at 10 cm. 15 seconds. 

 1 battery coil at 5 cm. 15 seconds. 

 1 battery coil at cm. 15 seconds. 



RIGHT SAPHENOUS 



mm. Hg. 



—6, mm. Hg. 



+2, -10 mm. Hg. 



+6, -12 mm. Hg. 



+8, -12 mm. Hg. 

 +22, -10 mm. Hg. 

 +22, -12 mm. Hg. 



RIGHT PERONEAL 



mm. Hg. 



— 1, mm. Hg. 



—4, +4 mm. Hg. 



+2, —6 mm. Hg. 

 + 14, -10 mm. Hg. 

 +20, -14 mm. Hg. 

 +22, -20 mm. Hg. 



(From experiment 47. Under brain compression.) 



THE JOURNAL OF COMPARATIVE NEDROLOGY, VOL. 30, NO. 4 



