. Dissection of the dog as a basis for the study of physiology . lion. It then passesthrough the diaphragm and continues as the abdomi-nal sympathetic, which also has ganglionic enlargementsas in the thorax. From these ganglia branches arisewhich form plexuses, similar to the solar plexus, forthe abdominal and pelvic organs. The two sympa-thetic trunks finally unite at the posterior end of thesacrum in an unpaired ganglion lying in the mid-line. 19. The Brachial Plexus in the dog is formed fromthe 6th, 7th and 8th cervical spinal nerves and theI St thoracic spinal nerve, and usually receives a


. Dissection of the dog as a basis for the study of physiology . lion. It then passesthrough the diaphragm and continues as the abdomi-nal sympathetic, which also has ganglionic enlargementsas in the thorax. From these ganglia branches arisewhich form plexuses, similar to the solar plexus, forthe abdominal and pelvic organs. The two sympa-thetic trunks finally unite at the posterior end of thesacrum in an unpaired ganglion lying in the mid-line. 19. The Brachial Plexus in the dog is formed fromthe 6th, 7th and 8th cervical spinal nerves and theI St thoracic spinal nerve, and usually receives a small DISSECTION OF THE NECK. 71 branch from the 2d thoracic spinal nerve. Shortlyafter emerging from the vertebral canal these nervesbranch to form a complicated plexus, represented inFig. 7, from which branches are given off to thearm, fore-arm, shoulder, etc. The plexus should bedissected upon the side the least injured by previousdissection ; in this case probably the right side. Cut TO CLAVO-DELTOIDSUPRA-SCAPULAR SUB-SCAPULAR MUSCULO-CUTANEOUS CIRCUMFLEX. )MUSCULO-SPIRAL ^ ^^^ES MAJOR ^Ot;s Fig. 7.—Diagram of the Brachial Plexus of the Dog. carefully through the muscles on the side of the verte-bral column where the neck and thorax meet until someof the nerves are exposed, and then from this traceout the other members of the plexus. In order toexpose the plexus fully one must take great care notto cut small branches, and must dissect slowly. Thefollowing are the chief terminal branches of the which of the spinal nerves they are derived canbe seen from the figure, although the arrangement ofthe plexus varies somewhat in different individuals,a. Branch distributed chiefly to the clavo-deltoid. 72 DISSECTION OF THE NECK. b. Supra-scapular Nerve to muscles on the dorsalside of the scapula. c. SuB-scAPULAR Nerve to musclcs on the ventralside of the scapula. d. MuscuLO-cuTANEous Nerve supplies the bicepsand may be traced finally to the elbow, where it breaksup int


Size: 1959px × 1276px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: ., bookcentury1800, bookdecade1880, bookpubli, booksubjectdissection