THE nOESE. 



175 



pass from the spine, between their respec- 

 tive vertebrae, and send branches to the 

 phrenic nerve, and ramifications to the mus- 

 cles, sympathetic nerve, and unite with the 

 dorsal. 



THE DIAPHRAGMATIC OR PHRENIC NERVE. 



This is formed by branches from several 

 of the cervical nerves. It takes its course 

 down along the inferior border of the scale- 

 nus muscle. It terminates by numerous 

 ramifications on the tendinous parts of the 

 diaplu'agm. 



DORSAL NERVES. 



These consist of eighteen pairs. They 

 pass from the vertebral canal in the same 

 manner as the cervical, having superior and 

 inferior branches. The inferior branches 

 follow the course of the intercostal blood- 

 vessels, and are called intercostal nerves. 

 The superior branches are distributed to 

 the back and loins. 



LUMBAR NERVES, 



Consist of five pairs (corresponding to 

 the number of the lumbar vertebrae). 



TJie first nerve ends in ramifications near 

 the stifle, and gives off branches to the last 

 dorsal nerve, to the sympathetic, and to the 

 second lumbar nerve. 



The second 7ierve has communication 

 with the first nerve, and sympathetic ; also 

 the crural. It sends one division to the fore 

 part of the haunch, where it becomes sub- 

 cutaneous, and ramifies over the stifle. The 

 other division crosses the ilio-lumbar artery, 

 just below its origin, and takes nearly a 

 similar course to the inward part of the 

 haunch, and then ramifies upon the skin ; in 

 its way it detaches a considerable branch, 

 called the spermaticus externus, which passes 

 through the abdominal ring, and sends 

 twigs, in the male, to the scrotum and tes- 

 ticle ; in the female, filaments go from it to 

 the uterus, udder, and external labia. 



The third nerve contributes to form the 

 crural and obturator. It sends small 

 branches to the sympathetic, psoas, and 

 obturator nerves. 



The fourth nerve sends a branch to the 

 sympathetic, contributes to the production 

 of the crural ; and also sends a branch to 

 the obturator. 



The fifth nerve communicates with the 

 sympathetic, crural, and sciatic plexus. 



SACRAL NERVES, 



Consist of five pairs; a superior and ir- 

 ferior fascicula. The superior make thej 

 exit through holes upon the upper part o 

 the sacrum, and are there buried under a 

 thick mass of muscle, and become cutane- 

 ous upon the outer part of the haunch. 



The inferior fascicula. — The first nerve 

 largely contributes to the origin of the 

 sciatic plexus, and sends a branch to the 

 gluteal nerve ; also to the sympathetic and 

 second lumbar nerves. The second nerve 

 communicates with the third and sympa- 

 thetic, and sends branches to the surround- 

 ing muscles and sciatic plexus. The third 

 and fourth have similar connections. The 

 fifth passes into the coccygeal muscles. 



COCCYGEAL NERVES. 



These issue from the spine, in the same 

 manner as the last described. They com- 

 municate with one another, are distributed 

 to muscles in the vicinity, and end in fila- 

 mentous ramifications at the end of the tail. 



NERVES OF THE FORE EXTREMITY. 



The fore extremity receives its nerves 

 from the axillary or humeral plexus, and 

 this plexus is formed by the union of por- 

 tions of the sixth and seventh cervical 

 nerves, 'and a division of the first dorsal 

 nerve. 



The external thoracic nerves, six or seven 

 in number, arise fi'om the humeral plexus, 

 and are distributed to the pectoral, triceps, 

 and other muscles ; they finally ramify into 

 the skin. 



The scapular nerves are called anterior, 

 posterior, and sub-scapular. The former 

 sends its ultimate filaments to the triceps. 



The posterior scapular nerve sends 

 branches to the sub-scapularis, triceps, teres 



