Volume 2

Manual of descriptive and pathological anatomy ... / Translated from the German into French, with additions and notes, by A.J.L. Jourdan ... and G. Breschet ... Translated from the French, with notes, by A.S. Doane, and others.

  • Meckel, J. F. (Johann Friedrich), 1781-1833
Date:
1839
Catalogue details

Licence: Public Domain Mark

Credit: Manual of descriptive and pathological anatomy ... / Translated from the German into French, with additions and notes, by A.J.L. Jourdan ... and G. Breschet ... Translated from the French, with notes, by A.S. Doane, and others. Source: Wellcome Collection.

    36/662 (page 28)
    It is formed of two lateral and perfectly similar halves, called hemit- pheres or lohes {hemispherce, hbi, Chaussier). These two halves are separated at their upper partby a longitudinal üssure {fissuralongitu- dinalis), much broader backward than forward; in the former direc- tion its breadth is half an inch, but hardly a line in the latter. They are, on the contrary, almost blended with each otber at their middle and lower portion. i Each hemisphere is divided into two lobe.s, (^lobilobuli, Chaussier), an anterior and a posterior. The anterior is more than twice as large as the posterior. They are separated by a groove more than an inch deep, the direction of which is oblique from above downward, and from bebind forward; this is called the groove of Sylvias (^fossa Sylvii), Heil terms it the valley. This Separation exists ouly below and on the side, for the groove does not extend to the upper face. The posterior lobe is also frequently divided into two others, termed the middle and posterior lobe. The latter forms that part of the cere- brum which rests on the tentorium. It cannot be distinguished exter- nally from the middle lobe, but is separated from it on its internal face by a fissure, the direction of which is obliquely from above downward, and from behind forward, and on the lower face by a slight depression. In each hemisphere we distinguish an inferior, an external, a Superior and an internal face. I. INFEKIOK FACE. § 1754. The inferior face should be examined first, for we fbere recognize most distinctly, that the cerebrum is directly continuous with the medulla oblongata. Of the three faces, this is the most irregulär, and its central portion is entirely separated from the two lateral parts. I. MIDULE REGION. I. CEREBRAl PEDUNCLES. § 1755. We first observe from behind forward, directly before the anterior edge of the annularprotuberance, (§ 1733) the cerebral peduii- cles, or the cr.ura of the medulla oblongata (^crura cerebri magna, crura ad medullam oblongaiam'). They are two large rounded bodies, about eight lines long, which become much larger from before backward, seven lines broad posteriorly, ten anteriorly, ten lines high, grooved longitudinally, and entirely formed of substance, white externally. They diverge from each other behind forward, and are separated at their lower part by a very broad and deep groove; this is only the anterior groove of the spinal marrow, which is deepened by the deve- lopment of the peduncles. This part forms above the floor of the aqueduct of Sylvius; its lower face is grey, and numerous vcssels pass through it, the direction of which is from below upward, and from without inward. Vicq-d’Azyr* terms it the middle perforated tubdance {substantia perforata media). * Loc. dt., p. 545.