branches which have a varicose appearance, form a rich plexus, and end in knobs. These organs are ound between the true skin and subcutaneous tissue of the fingers. 6. Organs of Golgi are found in tendons. Nerve fibres penetrate the tendon bundles and divide in a tree-like manner to end in little disks and varicosities. 7. Neuro-muscular spindles are small fusiform bundles of embryonic muscle fibres among which the nerve fibres end by encircling them and forming flattened disks. These are sensory endings, and must not be confused with the motor end plates. They are found in most of the striped muscles of the body. Motor nerves end in striped muscle by motor and plates. These are formed by a nerve fibre approaching a muscle fibre and suddenly losing its myelin sheath while its neurilemma becomes continuous with the sarcolemma of the muscle fibre. The axis cylinder divides, and its ramifications are surrounded by a disk of granular matter containing many clear nuclei. In very long muscle fibres more than one of these end plates are sometimes found. Involnntary motor endings are usualy found in sympathetic nerves going to unstriped muscle. The fibres form minute plexuses, at the points of union of which small triangular ganglion cells are found. After this the separate fibrils of the nerve divide, and each ends opposite the nucleus of an unstriped muscle cell. THE SYMPATHETIC SYSTEM This system is made up of two ganglia ted cords running down one on each side of the vertebral column and ending below in the median f0l|llS$|||F||l¢ c¢NTiK- lane f Gnnuuon CELL# ° 4 G Iwo Annu! s>..».»cu~.c if-pp., Svtmc-~»t, °"""'"“ Arrl.lEr¢' QTKTMUS In //N

f f f wsvsus Z ':A~smzN 1 '/ y * 6 ' can muon |l»» / w u-nl uncut From A. 'M. Paterson, in Cunningham's Tar!-Book af Anatomy. FIG. 4i*'SCh€l'I1€ of the Constitution and Connexions of the Gangliated Cord of the Sympathetic. The ganglia ted cord is indicated on the right, with the arrangement of the fibres arising from the ganglion cells. On the left the roots and trunks of spinal nerves are shown, with the arrangement of the white ramus communicants above and of the gray ramus below. vertebrae. In addition to these cords there are numerous ganglia and plexuses through which the sympathetic nerves pass on their way to or from the visoera and blood-vessels. A typical ganglion of the sympathetic chain is connected with its Corresponding spinal nerve by two branches called rami communioantes, one of which is grey and the other white (see fig. 4). The white consists of medulla ted fibres belonging to the central nervous system, and these are splanchnic afferent or centripetal, and efferent or centrifugal. The efferent fibres lie in the anterior roots of the spinal nerves, and, like all the fibres there, are either motor or secretory. They are the motor paths for the unstriped muscle of the vessels and viscera, and the 'secretory paths for the cells of the viscera. In the course of each fibre from the nerve cell in the spinal cord, of which it is an axon, to the vessel or viscus it supplies, there is always a break where it arborizes round a ganglion cell, and this may be in its own ganglion of the sympathetic chain, in a neighbouring ganglion above or elow, or in one of the so-called collateral ganglia interposed between the sympathetic chain and the viscera. In addition to these there are a certain number of vaso-dilator and viscero-inhibitory fibres, which run without any cell connexions from the spinal or cranial From A. M. Paterson, in Cuuningham's TgxffBook of A nalomy. FIG. 5.-jThe Distribution of the Sympat tic Gangliated Cord in the Neck. he Sy.I, Superior cervical ganglion, and con1.0, G.1>h, nexions and branches. Internal carotid artery. f nerve to the viscera. Va Qgosjgpharyngeal The splanchni c Hy' Hyioélossal

§ f;f“ébr;r afgnia; C.1, 2, 3, 4, First four cervical nerves.

Sens() nerves from Plex, Pharyngeal plexus. the rziscera and G.Ph, ~ Glosso-pharyngeal nerve. have no Cefl cOn E.C, To external carotid artery. - » Sy.2, Middle cervical ganglion, connexions nexions until they and b 1, anches rgicllga age tgglnoag C.5, 6, Fifth and sixth cervical nerves. if -g P I.Thy, Inferior thyroid artery. - ., 890' '°°'S Of the A V Ansa vieussenii i£;na'h§ e't;Vei};@f§ .Sy.3, Inferior cervical ganglion, conin ythe yan Hated nexions and branches. coid of gheg S m C.7, 8, Seventh and eighth cervical nerves. pathetic The Egres Vert, Vertebral plexus. of the white rami Car, Cardiac branches. communicant es are remarkable for their small diameter, and the efferent fibres, at all events, are only found in two regions, one of which is called the thoracic-lumbar stream and extends from the first or second thoracic to the second or third lumbar nerve, while the pelvic stream is found from the second to the fourth sacral nerves. The grey rami communicant es are found in connexion with all the spinal nerves, though they are irregular in the paths by which they reach the sympathetic ganglia from the cells of which they spring; their fibres are mainly non-medulla ted, and pass into both roots of the spinal nerves and also into the anterior and posterior primary divisions of those nerves. In this way they reach the body wall and limbs, and are somatic vaso-motor secretory and pilo-motor fibres, supplying the vessels, glands coccygeal ganglion (g. zmfpar). In the neck the cords lie in front of and hair muscles of the skin and its glands. The sympathetic the anterior tubercles o the transverse processes of the cervical ganglia, from which these nerves come, contain multipolar nerve vertebrae, in the thorax, in front of the heads of the ribs, while cells with one axon and several dendrites as well as a number of

in the abdomen-they lie in front of the sides of the bodies of the i medulla ted fibres passing' through, and much connective tissue.