THE LIVER. 57 



pression, to fit it to the projection of the vertebral column. The 

 ascending vena cava forms a superficial sulcus upon this mar- 

 gin, and frequently there is a complete canal through the sub- 

 stance of the liver for transmitting it. The right extremity is 

 very thick, and almost fills the hypochondriac region of 'that 

 side, while the left extremity is reduced to a thin, tapering, and 

 flexible edge. 



The under surface of the liver is much more irregular than 

 the upper; it is traversed in an antero posterior direction, in a 

 line corresponding with the attachment above of the suspensory 

 ligament, by the umbilical fissure, (Sulcus Umbilicalis) which 

 extends from the notch in the front edge to the depression be- 

 hind, arid obtains its name from having accommodated In the 

 foetal state, the umbilical vein, now converted into a round liga- 

 mentous cord. In the posterior part of this fissure is likewise to 

 be seen, in the same condition, what remains of the ductus ve- 

 nosus. The anterior portion of the umbilical fissure is not un- 

 frequently converted into a complete canal, by a portion of he- 

 patic substance crossing it like a small bridge. The transverse 

 fissure (Sulcus Transversus, Intermedius) is situated in the mid- 

 dle of the under surface of the liver, and extends along a third 

 or fourth of the long diameter of the latter. It begins some- 

 what to the left of the umbilical fissure, and crossing it at right 

 angles, proceeds towards the right extremity. It contains the 

 vena portarum, the hepatic artery, and the hepatic duct ; all 

 of which are bound to each other by a close cellular substance. 



The suspensory ligament above, and the umbilical fissure be- 

 low, give occasion to divide the liver into Lobes; Right and 

 Left; of which the right is by much the largest, and accommo- 

 dates almost entirely the transverse fissure, having also on its 

 under surface some subordinate elevations, to wit, the Lobu- 

 lus Spigelii and the Lobulus Quartus, together with the Gall- 

 Bladder. 



The Lobulus Spigelii is placed between the transverse fis- 

 sure and the posterior margin of the liver, to the right of the 

 posterior end of the umbilical fissure. Its shape is somewhat 

 prismatic, bifurcating in front; one of the elongations is a pa- 

 pilla overhanging the transverse fissure, and is, therefore, con- 

 sidered as one side of the gateway (portd) opened for the ve- 

 na portarum; the other elongation is a small ridge, sometimes 



