A description of the distribution of the nerves of the human body; with elementary physiological and surgical observations: including Mr. Brookes's nomenclature of the nervous system ... / by G.D. Dermott.

  • Dermott, G. D. (George Darby), 1802-1847.
Date:
1830
Catalogue details

Licence: Public Domain Mark

Credit: A description of the distribution of the nerves of the human body; with elementary physiological and surgical observations: including Mr. Brookes's nomenclature of the nervous system ... / by G.D. Dermott. Source: Wellcome Collection.

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    Jacobi. Which latter isa transparent mem¬ brane intercepting it from the Tunica Cho- roides. The Retina may be considered as consisting in itself,—of an External Stra¬ tum of Nervous Substance, which is in contact with the Tunica Jacobi, and in¬ tercepted by it from the Tunica Choroides —and a more Internal Stratum, which is a thin membrane, the vehicle to the ves¬ sels which nourish the nervous substance of the Retina, and termed the Tunica Vas- culosa Retinae. The External Medullary Lamina of the Retina ends upon the sur¬ face of the Canalis Petitianus, under the attachment of the Striae Ciliares, being im¬ pressed with the form of the Striae Ciliares; so as to lose itself in a striated form upon the surface of the Petitian Canal. The Tunica Vasculosa Retina: coursing forwards over the Petitian Canal, blends with the substance of the Tunica Chrystallina, just anteriorly to the Circumference of the lens. Third pair—or Motores Oculorum, Properly so called, arise from the in¬ ternal and posterior parts of the two Crura- Cerebri, immediately in front of the Pons Varolii. They pass directly forwards, so as to perforate the Dura Mater laterally to the Posterior Ephippial Processes. They are then continued through the External side of the region of the Cavernous Sinus in close cellular adhesion to the internal sur¬ face of the outer lamina of the Sphcenoidal Fold of the Dura Mater.—They are sub¬ sequently continued into the Orbits through the Foramina Lacera Orbitaria Superiora, and then part into Filaments, so as to supply the Levator Palpebrse Superioris: the Rectus Superior: Rectus Inferior: Rectus Internus: and the Obliquus Infe¬ rior : bestowing volition to these muscles ; a filament being appropriated to each. It also gives a filament to the Lenticular Ganglion. Fourth pair—or Nervi Pathetici. These are the smallest Cerebral Nerves; and they have erroneously been said to be composed, individually, of a single fila¬ ment of nervous substance. They arise from the posterior sides of the Testes, just above the attachment of the Valvula Magna Vieussenii; being supposed to take up their substance from the continuation of the Respiratory Tract of Nervous Matter.* They wind outwards around the posterior sides of the Testes, just above the attach¬ ment of the Valvula Magna Vieussenii: * Their origins are seen when the Vulvula Magna Vieussenii is first exposed, by the re¬ moval of the united parts of the Lobes Cere- belli lying over the Valve of Vieussens. they then slant obliquely downwards and forwards, by the side of the Iter a Tertio ad Quartam Ventriculam; and emerge at the Base of the Brain, laterally to the side of the Pons Varolii (which forms the floor of the passage:) they are then continued forwards, and emerge from beneath the Anterior Semicircular Edge of the Tento¬ rium : they pierce the Dura Mater late¬ rally to the Posterior Ephippial Processes, a little more laterally than the Third Pair, and immediately beneath the Cor¬ nua, or the sides of the Anterior Edge of the Tentorium. Each is subsequently continued forwards with the Motor Oculi of the third Pair, through the outer side of the Region of the Cavernous Sinus, and in close adhesion to the internal surface of the outer layer of the Sphenoidal Fold, like the Motor Oculi; but ranging superiorly to it. It then inclining obliquely inwards, crosses over the Motor Oculi, (in the re¬ gion of the Cavernous Sinus,) next passes through the Foramen Lacerum Orbitale Superius, and plunges abruptly into the substance of the Obliquus Superior, or Trochearis Muscle; being supposed to im¬ part Respiratory Action to that muscle. Fifth pair—or Nervi Trigemini, or Par Trigemini. These and the Optic Nerves, are the largest of the Cerebral Nerves. They are of a flat tape-worm-like figure; and they are termed the Spinal Nerves of the Head. They individually come off in the form of a double root;—one portion of which is derived from the Tract of Medullary Sub¬ stance in the Base of the Brain, which is a continuation of the Medullary Column of the Spinal Marrow imparting Common Sensation;—the other from a Tract, a si¬ milar continuation of the Column of the Spinal Marrow which imparts Volition: and so that this is represented as a Com¬ pound Nerve; or as being for the purpose of imparting Common Sensation and Vo¬ lition to the soft and muscular parts of the head; just as the Spinal Nerves are Com¬ pound Nerves, and are for the purpose of imparting Common Sensation and Volition to the soft and muscular parts of the Frame at large. These nerves pass off from the outer side of the union of the Pons Varolii with the Crura Cerebelli: they course ob¬ liquely forwards and outwards, and pierce the Dura Mater some distance laterally to the Posterior Ephippial Processes, more laterally than the Third or Fourth Pair of Nerves and beneath the edge of the Tento¬ rium. Each then expands upon the ex¬ tremity of the Petrous Portion of the Tem¬ poral Bone into a flat Semilunar-shaped Ganglion, termed the Ganglion Gasse-