Quarterly journal of microscopical science . ing apparently from the folds just spoken of. One of thelayers, Jc, forms the proper roof of the new cavity, while the 62. other is continuous, and forms a part of the cells constitutingthe walls of the whole body. This new cavity or incompletetube is the rudiment of the embryonic nervous system, andmay, therefore, be called the neural tube. Between it andthe alimentary tube at the hind part of the body a newstructure has now made its appearance—the row of largecells s, the immediate origin of which is uncertain. Thisrow of cells is the rudiment of
Quarterly journal of microscopical science . ing apparently from the folds just spoken of. One of thelayers, Jc, forms the proper roof of the new cavity, while the 62. other is continuous, and forms a part of the cells constitutingthe walls of the whole body. This new cavity or incompletetube is the rudiment of the embryonic nervous system, andmay, therefore, be called the neural tube. Between it andthe alimentary tube at the hind part of the body a newstructure has now made its appearance—the row of largecells s, the immediate origin of which is uncertain. Thisrow of cells is the rudiment of the axis band (or notochord)of the tail. The embryo now becomes bent at its hind part, the bend-ing takes place more on the left side than the right; and thebent portion grows more rapidly than the rest of the body,thus giving rise to the tail. The stage represented in fig. 4 is now soon reached. Thedigestive tube h, with its thick walls, occuj)ies the fore partof the body; immediately above it is the neural cavity n,wider and more capaci
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Keywords: ., bookcentury1800, bookdecade1870, bookpublisherlondo, bookyear1870
