The development of the human body; a manual of human embryology . prm - !V ^^ ? ** en!en prm 0M§&gg&W> VlVf-iLTV—t Fig. 26.—Longitudinal Sections through Embryos of the Gecko, showing Gastrulation. ec, Ectoderm; en, secondary endoderm; en, primary endoderm; prm, prostomial mesoderm.—{Will.) it comes to lie within the archenteron. In some turtles,on the other hand, the disappearance of the floor of theinvagination takes place at a very early stage of theinfolding, the roof cells only persisting to grow forward toform the dorsal wall of the archenteron. This interest-ing abbreviation of the p
The development of the human body; a manual of human embryology . prm - !V ^^ ? ** en!en prm 0M§&gg&W> VlVf-iLTV—t Fig. 26.—Longitudinal Sections through Embryos of the Gecko, showing Gastrulation. ec, Ectoderm; en, secondary endoderm; en, primary endoderm; prm, prostomial mesoderm.—{Will.) it comes to lie within the archenteron. In some turtles,on the other hand, the disappearance of the floor of theinvagination takes place at a very early stage of theinfolding, the roof cells only persisting to grow forward toform the dorsal wall of the archenteron. This interest-ing abbreviation of the process occurring in the geckoindicates the mode of development which is found in themammalia. ;o THE DEVELOPMENT OF THE HUMAN BODY. The existence of a prostomial mesoderm in connectionwith the primitive streak has already been noted, andwhen the invagination takes place it is carried forward asa narrow band of cells on each side of the sac of secondaryendoderm. After the absorption of the ventral wall ofthe invagination a folding or turning in
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectembryol, bookyear1902
