TBAXSECTIOX OF THE THORAX. 



397 



Gng. thyr., Ganglion thyroideum — The thyroid or middle cervical ganglion of the 

 sjnnpathic (Fig. 107, 108. § 1043). 



Gng. vrt., Ganglion vertebrale — The vertebral or inferior cervical ganglion of the 

 gympathic (Fig. 107, 108, § 1043). 



Myelon — The myelon or spinal cord is the part of the central nerv^ous system situated 

 within the neural canal (Fig. 104, § 479K 



MM. Ig. colli — The longns colli muscles. 



N. thr. (1st) — The first thoracic or dorsal nerve. The abbreviation is written on the 

 ventral primary division. Centrad of the abbreviation, the dorsal primary division is seen 



"o^^V.v. brtpk. 



Fig. 109. — Transection of the Thorax, showing the Origin of a Pair of Spinal 

 Nerves and the Relations of the Sympathic and Cerebro spinal Systems ; 

 Cephalic View ; x 1.5. 



to join the ventral, and the trunk is formed by the union of the dorsal and ventral nerve 

 roots from the myelon (§ 1007). 



N. thr. (2d), N. thoracicus (2d) — The second thoracic nerve, showing the ramus com- 

 municans connecting it with the vertebral ganglion. 



N. sym. (cd.) i, N. sympathicus (caudalis) — The sympathic nerve extendingr caudad 

 of the vertebral ganglion in the thorax (Fig. 107, § 1043). 



Ramus communicans 2 — The communicating branch between the vertebral ganglion 

 of the sympathic and the 2d thoracic myeloual nerve. 



