516 O. LARSELL AND M. L. MASON 
SUMMARY AND CONCLUSIONS 
The vagus nerves supply the preganglionic fibers to the in- 
trapulmonary ganglion cells which are scattered along the 
bronchi and their branches, as is shown by the disappearance of 
most of the pericellular networks about these cells following 
experimental degeneration of the vagus nerve of the same side. 
Most of these preganglionic fibers come from the vagus of the 
homolateral side, but some pericellular networks remain in the 
lung after degeneration of the vagus of the same side. These 
are probably derived in part from the contralateral side by the 
crossing over of fibers through the posterior pulmonary plexus. 
The number of fibers in the bronchial musculature which 
take the stain is affected very little, if at all, by the degeneration 
of the fibers of the vagus nerve. 
A few sensory terminations remain in the lung of the operated 
side after degeneration of the vagus fibers leading to it. These 
endings are believed to be derived, in part, from the vagus of the 
opposite side. 
The number of nerve fibers in the walls of the pulmonary 
blood-vessels which take the stain is unaffected by degeneration 
of the vagus nerve. 
In conclusion we desire to express our thanks to Dr. 8. W. 
Ranson for valuable suggestions in the course of the work on 
which the present paper is based. 
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LARSELL, O. 1921 Nerve terminations in the lung of the rabbit. Jour. Comp. 
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Moxuant, M. 1913 Les ganglions périphériques du vague. Le Névraxe, T. 15, 
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