Quain's elements of anatomy . tube between it and the remauiing part of the vesicle whichforms the medulla oblongata. At the same time that these changes are progressing, two otherremarkable phenomena occur, which, as presenting themselves very con-stantly in the brains of vertebrates, and having important morphologicalrelations, may be mentioned at this place. These phenomena are both re-lated to the thalamencephalon, and they consist, 1st, in the downwardprojection of a pointed funnel-shaped part of the cerebral wall, with aprolongation of the ventricular canity within it, into the pituitary
Quain's elements of anatomy . tube between it and the remauiing part of the vesicle whichforms the medulla oblongata. At the same time that these changes are progressing, two otherremarkable phenomena occur, which, as presenting themselves very con-stantly in the brains of vertebrates, and having important morphologicalrelations, may be mentioned at this place. These phenomena are both re-lated to the thalamencephalon, and they consist, 1st, in the downwardprojection of a pointed funnel-shaped part of the cerebral wall, with aprolongation of the ventricular canity within it, into the pituitary fossa, Fig. 72S. LOXGITUDINAL SECTION THROUGH THE BRAIN OP SCTLLIUM CANICULA AT ANADVANCED STAGE OF DEYELOPJIEKT. (From BaKour.) ccr, cerebral hemisphere ; fn, pinealgland; , optic thalamus ; op, opticchiasma ; pt, ijituitary body ; in, infundi-bulum ; cb, cerebellum ; , recessusrestibuli, or passage from the auditoryvesicle to the exterior ; met, medulla ob-longata; , internal cai-otid artery. Fig. 728. JP^L *. preparatory to its union with the evoluted part of the mouth cavity by which the pituitary gland takes its rise; and 2nd, in the thinning of the dorsal wall of the brain, and the prolongation of a part of that wall, which in the lower vertebrates reaches the cranial roof by a peculiar tubular extension, and is the homologue of the pineal gland. There are thus distinguished the rudiments of five ftmdamental con-stituents of the brain, under which it will be found convenient to bring Fig. 729.—Outline op a Fig. 729. LONGITUDINAL SECTION THROUGH THE BRAIN OFA CHICK OF TEN DATS. (After Mihalkovics.) h, cerebral hemisphere ; olf,oKactory lobe and nerve ; st,corpus striatum ; Iv, lateralventricle; ac, anterior com-missure ; It, lamina terminalis;ope, optic commissure ; pit,pituitary gland ; inf, inf undi-bulum; cai, internal carotidartery ; v^, third ventricle ;ch?, choroid plexus of third ventricle ; pin, pineal gland; Ijg, corpora bigemina; amv, anterior me
Size: 1605px × 1557px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., boo, bookcentury1800, booksubjectanatomy, booksubjecthumananatomy
