A System of midwifery : including the diseases of pregnancy and the puerperal state . External surface of theovum, showing the 104 DEVELOPMENT OF THE OVUM. [CHAP. appearance of definite embryonic structure is a shallow groove lyinglengthwise in the area pellucida. This is the primitive trace, the earliest indication of the cerebro-spinal canal. If viewed insection, this groove ( a ) is scon to lie betweentwo lateral eminences calledthe lamince dorsales (c <?).which we here demonstrate, Diagram showing the earliest formation of the embryos . as it illustrates a law in
A System of midwifery : including the diseases of pregnancy and the puerperal state . External surface of theovum, showing the 104 DEVELOPMENT OF THE OVUM. [CHAP. appearance of definite embryonic structure is a shallow groove lyinglengthwise in the area pellucida. This is the primitive trace, the earliest indication of the cerebro-spinal canal. If viewed insection, this groove ( a ) is scon to lie betweentwo lateral eminences calledthe lamince dorsales (c <?).which we here demonstrate, Diagram showing the earliest formation of the embryos . as it illustrates a law in de-velopment, of which, in the evolution of special organs, we find many illustrations. This diagram, after Remak, is the only one in the seriesin which the middle layer is indicated, showing at o the first trace ofthe vertebral column, and at p p the subdivision of this layer, indicat-ing the origin of the pleuro-peritoneal cavity. The lowest in the figureis the mucous layer. In the development of the tube of which thegroove is the trace, the laminae dorsales rise, and, folding together, meetin the middle line, and there unite. Conseq
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectobstetrics, bookyear1
