Parietal branches limited in dimension which ramify on the ventral surface of the sacrum, especially in relation with the sacral artery, forming what I have termed the plexus intertrunci sacralis. The four segments of the trunk of the sympathetic nerve, cervical, dorsal, lumbar and sacral, differ according to location and environment. The distributing branches of the pelvic sympathetic trunk are the least important of any segmental trunk. The bilateral cervical sympathetic trunks are united by two localized prevertebral plexuses, the pharyngeal and cardiac. The bilateral dorsal sympathetic trunks are united by a single prevertebral colossal pelvus-abdominal brain.
Ganglionic coalescence occurs chiefly in the cervical trunk.
The ganglia are the most irregular in the pelvic trunk, the largest in the cervical and lumbar trunks. The commissural cords are multiple supernumerary in the lumbar and sacral trunks only. The trunk of the vasomotor nerve here presented was dissected under alcohol with care as regards connexions and relations. The ellipse formed by the two lateral trunks is evident. The ellipse extends from the cranium to the coccyx.