The development of the human body; a manual of human embryology . nnected with it, the loop projecting ventrally into theportion of the ccelomic cavity which is contained within theumbilical cord, and being placed so that its upper limblies to the right of the lower one. Upon the latter a slightpouch-like lateral outgrowth appears which is the begin-ning of the cacum and marks the line of union of the fu-ture small and large intestine. The small intestine, con-tinuing to lengthen more rapidly than the large, assumes asinuous course (Fig. 169) in which it is possible to recog-nize six primary c
The development of the human body; a manual of human embryology . nnected with it, the loop projecting ventrally into theportion of the ccelomic cavity which is contained within theumbilical cord, and being placed so that its upper limblies to the right of the lower one. Upon the latter a slightpouch-like lateral outgrowth appears which is the begin-ning of the cacum and marks the line of union of the fu-ture small and large intestine. The small intestine, con-tinuing to lengthen more rapidly than the large, assumes asinuous course (Fig. 169) in which it is possible to recog-nize six primary coils which may be recognized until ad- 320 THE DEVELOPMENT OF THE HUMAN BODY. vanced stages of development and even in the adult(Mall). The first of these is at first indistinguishablefrom the pyloric portion of the stomach and can be recog-nized as the duodenum only by the fact that it has con-nected with it the ducts of the liver and pancreas; as de-velopment proceeds, however, its caliber diminishes and itassumes the appearance of a portion of the Fig. 169.—Reconstruction ok Embryo of 20 ; K, kidney; L, liver; S, stomach; SC, suprarenal bodies;II7, mesonephros.—(Mall.) The remaining coils elongate rapidly and are throwninto numerous secondary coils, all of which are still con-tained within the ccelom of the umbilical cord (Fig. 170).When the embryo has reached a length of about 40 coils rather suddenly return to the abdominal cavity, THE INTESTINE. 321 and now the caecum is thrown over toward the right, sothat it comes to lie immediately beneath the liver on theright side of the abdominal cavity, a position which it re-tains until about the fourth month after birth (Treves).The portion of the large intestine which formerly pro-jected into the umbilical ccelom now lies transverselyacross the upper part of the abdomen, crossing in front ofthe duodenum and having the remaining portion of thesmall intestine below it. The elongation continuing, the
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectembryol, bookyear1902
