TRANSECTION OF TBE THORAX. 



397 



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

 sympathic (Fig. 107, 108, § 1043). 



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

 sympathic (Fig. 107, 108, § 1043). 



Myelon — The myelon or spinal cord is the part of the central nervous system situated 

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



MM. Ig. colli — The longus colli muscles. 



N. thr. (ist) — 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 



Pig. 109.— Tbansection of the Thoeax, showtng the Origin of a Paik of Spinal 

 Nerves and the Relations of the Sympathic and Ceeebeo-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. (zd), N. thoracicus (2d) — The second thoracic nerve, showing the ramus com- 

 municans connecting it with the vertebral ganglion. 



N. syra. (cd.) i, N. sympathicus (caudalis) — The sympathic nerve extending caudad 

 of the vertebral ganglion in the thorax (Fig. 107, § 1042). 



Ramus communicans 2 — The communicating branch between the vertebral ganglion 

 of the sympathic and the 3d thoracic myelonal nerve. 



