560 FCTTTAL LIVEE AND KIDNEYS. 



TCETAL LIVER. 



The Liver is the first formed organ in the embryo. It is deve- 

 loped from the alimentary canal, and, at about the third week, fills 

 the whole abdomen, and is one half the weight of the entire embryo. 

 At the fourth month the liver is of immense size in proportion to the 

 bulk of the fetus. At birth it is of very large size and occupies the 

 whole upper part of the abdomen. The left lobe is as large as the 

 right, and the falciform ligament corresponds with the middle line 

 of the body. The liver diminishes rapidly after birth, probably from 

 the obliteration of the umbilical vein. 



KIDNEYS AND SUPRA-RENAL CAPSULES. 



The Kidneys present a lobulated appearance in the fetus, which 

 is the permanent type amongst some animals, as in the bear, the 

 otter, and cetacea. 



The Supra-renal capsules are organs which appear, from their 

 early and considerable developement, to belong especially to the 

 economy of the foetus. They are distinctly formed at the second 

 month of embryonic life, and are greater in size and weight than 

 the kidneys. At the fourth month they are equalled in bulk by the 

 kidneys, and at birth they are about one-third less than those organs. 



VISCERA OP THE PELVIS. 



The Bladder in the fetus is long and conical, and is situated alto- 

 gether above the upper border of the os pubis, which is as yet small 

 and undeveloped. It is, indeed, an abdominal viscus, and is con- 

 nected superiorly with a fibrous cord, called the urac/ius, of which 

 it appears to be an expansion. 



The Urachus is continued upwards to the umbilicus, and becomes 

 connected with the umbilical cord. In animals it is a pervious duct, 

 and is continuous with one of the membranes of the embryo the 

 allantois. It has been found pervious in the human fetus, and the 

 urine has been passed through the umbilicus. Calculous concretions 

 have also been found in its course. 



The Uterus, in the early periods of embryonic existence, appears 

 to be bifid, from the large size of the Fallopian tubes, and the small 

 developement of the body of the organ. At the end of the fourth 

 month the body assumes a larger bulk, and the bifid appearance is 

 lost. The cervix uteri in the fetus is larger than the body of the 

 organ. 



The Ovaries are situated, like the testicles, in the lumbar region, 

 near to the kidneys, and descend from thence gradually into the 

 pelvis. 



