. Manual of antenatal pathology and hygiene : the foetus. at itis in the adult; but the facts are difficult to get, for the topographyof the brain of the unborn foetus is practically unknown, and it ismanifestly fallacious to draw conclusions from the moulded headafter birth. The following statements, therefore, may requirerevision. The Sylvian fissure is at a higher level in the foetus,and lies above the squamous suture instead of coinciding with it asin the adult; it has been stated that the lower end of the fissureof Eolando lies in front of the coronal suture in the foetus, butmy observati
. Manual of antenatal pathology and hygiene : the foetus. at itis in the adult; but the facts are difficult to get, for the topographyof the brain of the unborn foetus is practically unknown, and it ismanifestly fallacious to draw conclusions from the moulded headafter birth. The following statements, therefore, may requirerevision. The Sylvian fissure is at a higher level in the foetus,and lies above the squamous suture instead of coinciding with it asin the adult; it has been stated that the lower end of the fissureof Eolando lies in front of the coronal suture in the foetus, butmy observations do not support this opinion, although they showthat the fissure is apparently less vertical than in later life; theparieto-occipital fissure corresponds with some accuracy with thetip of the occipital bone at the posterior fontanelle, and lies behindrather than in front of the lamljdoidal suture; and the calcarinefissure is situated approximately opposite the occipital has been said that the cerebrum overlaps the cerebellum to a less. Fig. 16. 102 ANTENATAL PATHOLOGY AND HYGIENE extent in the fcetus, but my sections do not show this peculiarity (Figs. 17 and 18). The cerebralconvolutions areless complex inthe foetus than inthe adult, and thesulci are less may be thatsome accessoryfissures are notdeveloped tillafter birth, andare thereforepostnatal forma-tions, but aboutthis matter thereis little know-ledge. The studyof the minuteanatomy of thefoetal brain hasrecently receiveda great impulseby the discoveryof Flechsig thatthere is a correla-tion between thefunctions of sys-tems of neuronesand the myelina-tion of theiraxons: in the full-time fcetus, thewhole afferenttract conveyingtactile, articular,muscular, andvisceral sensa-tions by the pos-terior columns,fillet, thalamus,and corona radi-ata is myelinated;and it follows, ifthe hypothesis ofFlechsig be cor-rect, that impres-sions have, duringbeen passing along
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectfetus, bookyear1902