AUTHOR'S ABSTRACT OF THIS PAPER ISSUED 
BY THE BIBLIOGRAPHIC SERVICE, MAY ll 
AN EXPERIMENTAL ANALYSIS OF THE SYMPATHETIC 
TRUNK AND GREATER SPLANCHNIC NERVE 
IN THE CAT 
S. W. RANSON anv P. R. BILLINGSLEY 
Anatomical Laboratory of the Northwestern University Medical School! 
TEN FIGURES 
A consideration of the facts presented in the preceding paper 
makes it clear that much could be learned through the study of 
the sympathetic trunk and splanchnic nerves after a variety 
of experimental lesions leading to the degeneration of nerve 
fibers arising from the spinal cord and spinal ganglia. We have 
five experiments to record, and since no two were just alike it 
will be best to consider each separately. The operations were 
performed under rigid asepsis. The general technique of expos- 
ing the spinal cord and nerve roots has been given in another 
place (Ranson and v. Hess, 715). After time had been allowed 
for degeneration, the lesion was verified at autopsy and the 
affected portion of the sympathetic trunk with its rami com- 
municantes and the greater splanchnic nerve was removed and 
prepared for microscopic examination by fixation in osmic acid 
or by the pyridine silver technique. So far as was possible the 
material was cut into serial sections. The details of the five 
experiments follow. 
Cat XI. Died seven days after the left sympathetic trunk was 
cut below the ninth thoracic ganglion and the ninth thoracic to 
the first lumbar spinal nerve roots cut proximal to the spinal 
ganglia as shown in figure 1. Examination of the gray rami of 
the tenth, eleventh, and twelfth thoracic nerves, showed that 
the few fine myelinated fibers which they normally contain were 
not in the process of degeneration. That is to say, these are not 
1 Contribution No. 59, February 15, 1918. 
441 
