NERVE TERMINATIONS IN THE LUNG IS, 
experimental side as compared with the intact side. The source 
of these fibers, according to Méllgaard, is the second and third 
thoracic ganglia of the sympathetic trunk, chiefly of the homo- 
lateral side, but also from the ganglia of the opposite side. We 
have nothing to add to this statement. The nerve processes of 
the pulmonary vessels are probably all postganglionic fibers. 
No exhaustive study was made of the sections from the ex- 
perimental side with reference to sensory nerve terminations. 
However, a few such endings were observed at some of the 
stations which have been found to be characteristic (Larsell, ’21). 
Also a few large nerve fibers (fig. 5, s. fi.) may be followed for 
considerable distances along the bronchial tree in the lung of the 
experimental side. 
These sensory terminations and the fibers of large size which 
probably lead to them are very likely derived, in large part, 
from the vagus of the opposite side, although Mollgaard, in the 
article previously cited, has brought forth evidence that the 
lung receives sensory fibers also from the second and third 
thoracic spinal gangla. The physiological experiments of 
Barry (13) and Roger (717) clearly demonstrate that afferent 
impulses from the lung travel through the sympathetic trunk 
and white rami communicantes to the spinal cord. Accordingly, 
some of the sensory fibers and their terminations which remain 
in the lung after degeneration of the vagus branches leading to 
it may have their origin in the second and third thoracic spinal 
gangha. Both Mollgaard (?12) and Molhant (13) state that 
the origin of the sensory fibers which pass to the lung by way of 
the vagus nerve is in the body of the ganglion nodosum, well 
above the level at which the vagotomy was performed. Hence 
it is not likely that any aberrant cells from this ganglion were 
responsible for the sensory terminations which remained in the 
lung after degeneration of the lower part of the vagus leading to it. 
