156 



F. H. SCOTT. 



3. The third set of experiments were made in view of the possibility 

 that the difference in the action of the two roots might be due to a 

 better blood supply and not to the nerve cells themselves. The two 

 corresponding nerves were cut in the plexus and the ganglion on each 

 side carefully dissected free so that both nerves with their ganglia were 



Fig. 8. 



Fig. 9. 



Fig. 10. 



Fig. 8. Upper line from root, lower from nerve in plexus. Only the first contraction in 

 upper line is from the cut root, all the others (marked A") are from the opposite side 

 (crossed reflexes) as can be clearly seen when the longer interval was allowed. The 

 cut root is also seen to have caused a crossed reflex in lower line (first contraction). 



Fig. 9. Upper line tracing from unligatured, lower from ligatured root. It is seen there 

 are no contractions from the ligatured root. The contractions (marked X) in the 

 lower line are crossed reflexes from the unligatured root. 



Fig. 10. Reflexes from dorsal root belonging to same side as upper tracing. Time of 

 stimulation 2 minutes. Lower tracing is the crossed reflex. 



connected to the cord by their roots only and were thus equal as regards 

 blood supply. A thread was bound tightly around one root and the 

 whole dissection kept moistened with oxygenated frog's blood diluted 



