BiiOMAN und RiETz, Verdauungsrohr. 519 



tlie rif;ht side of thc duudenal inesentery there was a large peritoneal recess or poui-h the niouth of which was directed 

 anteriurly, and to wliicli reference has already been niade. 



The duodeno-iejunal flexure lay immediately to the left side of the vertebral cohimn and marked tlie beginniiis of the 

 mesentery proper and of the small intestine suspended in it. This mesentery had a very short base wliich practicaliy cor- 

 responded to the entrance of the superior mesenteric vessels. It was twisted to the right and supportcd tlie jejnnuin and 

 ileiim. which together nicasured alniost 46 feet in length. 



Tlie coecal diverticulum fonnerly referred to as representing the combined coecum and veriniforni ajipendix, was taken 

 to indicate the ternünation of the small and the beginning of the large intestine. This )iriinitive developmental form of the 

 coecum and vermiform was rather niore than an inch in length, while in calibre it corresponded witli the gut. From this 

 diverticulum to the end of the gut there were no other external evidences of any distinction between small aud large 

 intestine. 



From the coecum the large intestine or c o 1 o n persued the first 9 inches of its course suspended iu the same mesen- 

 tery as the small intestine. Thereafter the colon assumed a mesial position and, as far as the pelvic, i. e. for a distance of 

 18 inches, it was suspended in a dorsal mesial mesentery. The pelvic portion of the colon was also placed mesially. and 

 the greater part of it was also suspended in a dorsal mesentery. From the pelvic inlet to the anal aperture the gut measured 

 nearly 10 inches, so that the entire length of the colon from coecum to anus was practicaliy 3 feet. Thus the total length 

 of the gut from pylorus to anus was: — 



Duodenum 1 foot. 



Small intestine 4(J feet. 



Colon ;5 feet. 



Total 50 feet. 



The 1 i V e r was large and deeply fissured, thereby prcsenting very distinct lobes. It was intimately associated with 

 the diaphragm, and occupied the anterior end of tlie abdominal cavity from side to side. It was provided with the usual 

 peritoneal ligaments. The falciform and coronary ligaments presented no special features as regards their arrangement, but 

 the left lateral ligament extended from the sharp left niargin of the hver whereas the right lateral ligament was short and 

 extended from the smooth surface of the right aspect of the right lobe. The diapliragmatic surface of the liver was smooth 

 and convex, adapting itself to the abdominal surface of the diaphragm and presenting right and left lobes in relatioii to the 

 suspensory or falciform ligament. The right lobe was divided into mesial and lateral portions by a deep dorso-ventral fissure, 

 and the left lobe was imperfectly divided by dorsal and ventral notches which, however, did not meet each other. 



On its visceral aspect the hver was much subdivided, particularly in relation to the right lobe. The right and left 

 lobes were marked off from each other by the ligamentum teres (obliterated umbihcal vein) on the ventral aspect of the 

 hilum, and by the hcpatic sinus on the dorsal aspect of the hilum. The right lobe presented the same mesial and lateral, 

 portions which were noted on the diapliragmatic aspect. The mesial portion was divided into dorsal and ventral parts by 

 the hilum. To the ventral portion the gall-bladder was attached, and this part of the right lobe was connected to the left 

 lobe by a pons hepaticae. The dorsal portion was to a large extent concealed by the large hepatic sinus. The lateral part 

 of the right lobe was also divided into dorsal and ventral segments by the extension of the hilum across its visceral aspect. 



A tailed lobe extending from the dorsal segment of the mesial portion of the right lobe, j)assed backwards on the 

 ventral surface of the inferior vena cava, which was thus embedded in the liver substance. This tailed lobe cxpanded so 

 as to conceal a eonsiderable length of the inferior vena cava, and into this hidden part of the cava there opened directly 

 the hepatic veins from this particular lobe, as also the hepatic veins from the lateral part of the right lobe. 



The inferior vena cava itself opened into the large hepatic sinus situated close to the diaphragm and extending right 

 and left of the suspensory hgament. This sinus received the hepatic veins from the right and left lubes of the liver, with thc 

 exception of those veins already mentioned as opening directly into the inferior vena cava. The inferior of this sinus was 

 imperfectly divided into right and left parts by a crescentie partition which was situated to the right side of the line of 

 attachment of the suspensory hgament, so that the part of the sinus to the left side of the crescentie fold was the larger. 

 The inferior vena cava opened into the hepatic sinus on the right side of the imperfect partition, while on its left side it 

 received the mouth of the ductus venosus. 



The hepatic sinus narrowed for the purpose of passing through the diaphragm in order to enter the right auricle of 

 the heart, but the general size of its lumen was so much greater than that of the inferior vena cava that it is more accu- 

 rate to say that the inferior vena cava opened into the sinus and the sinus joined the auricle. 



The conditions presented by the hepatic veins afford some interesting Ught upon the question of their development. 

 Clearly the large hepatic sinus has resulted from the fusion of the two embryonic venae revehentes, although, from the 

 Position of the imperfect crescentie partition, it is evident that the left vena revehens was the larger of the two and therefore 

 received the smaller or right vena revehens. This arrangement would therefore appear to provide a Variation upon the cur- 

 rent statement that ,,the left vena revehens loses its connection with the sinus venosus and opens into the right vena reve- 



66* 



