434 S. W. RANSON AND P. R. BILLINGSLEY 
the internal carotid nerve. These were all under 4.54 except 
two, which measured 6y. Large myelinated fibers were found 
in both limbs of the subclavian ansa which joined to form a single 
trunk just below the middle cervical ganglon. <A cardiac 
branch given off by the trunk in this position contained a con- 
siderable number of fibers between 4.5 and 7u. We counted 
forty-eight that measured approximately 6. Aside from the 
presence of these larger fibers, this nerve had the same structure 
as the cardiac branch of the stellate ganglion. These observa- 
tions indicate that the large myelinated fibers pass through the 
stellate ganglion, run in both limbs of the ansa, and leave through 
the cardiac branch coming from the middle cervical ganglion or 
from the ansa subelavia. This is in keeping with the work of 
Edgeworth (92), who found that the large myelinated fibers in 
the dog could be followed in the stellate ganglion through the ansa 
subelavia and middle cervical ganglion, whence they were dis- 
tributed to the heart and lungs. This question deserves thor- 
ough study. As is indicated in figure 4 B, the sensory fibers 
from the lower eight thoracic rami run downward in the trunk 
and out through the splanchnic nerve. In the segments Just be- 
low the stellate ganglion there are few large myelinated and un- 
myelinated sensory fibers, as is indicated in the diagram by the 
dotted line. 
THE GREATER SPLANCHNIC NERVE 
At another time we expect to take up the more detailed con- 
sideration of all the splanchnic nerves of the cat, but the present 
paper would not be complete without some account of the struc- 
ture of the first and largest of the series, the greater splanchnic 
nerve. <A study of serial sections through the trunk at the point 
of origin of this nerve shows clearly that it is formed by the 
separation of a large part of the oval well myelinated fascicle 
from the rest of the trunk. The nerve has the same structure 
as this oval fascicle and consists of large and small myelinated 
and unmyelinated fibers in the same proportion and with the same 
arrangement as in that fascicle. 
