\NNEKED T ////: i/:/"-u/vi/. DIGKSTtVS CANAL. \>>1 



rtion of blood contained within these two sots of vessels ; and so lon^ 

 as the cireulatiou is natural, the colour will 1>^ uniform. But tho instant 

 that any cause is developed which shall interfere with tho free circula- 

 tion of either, there will bo au immediate diversity in tho colour of tho 

 lobule. 



Thus, if there bo any impediment to tho free circulation of the venous 

 blood through the heart or lungs, tho circulation in tho hepatic veins will 

 be retarded, and the sublobular (or supralobular) and intralobular veins 

 will become congested, giving rise to a more or less extensive redness in the 

 c, 'lit re of each of the lobules ; while the marginal or non-congested portion 

 presents a distinct border of a yellowish white, yellow, or green colour, 

 according to the quantity or quality of tho bile it may contain. " This is 

 ' passive congestion' of the liver, the usual and natural state of the organ 

 after death ;" and, as it commences with tho hepatic vein, it may be called 

 the first stage of hepatic venous congestion. 



But if the causes which produced this state of congestion continue, or bo 

 from the beginning of a more active kind, the congestion will extend through 

 tho lobular venous plexuses " into those branches of the portal vein situated 

 in the iiitcrlobnlnr fissures, but not to those in the spaces, which being larger, 

 and giving origin to those in tho fissures, are the last to be congested." In 

 this second stage the liver has a mottled appearance, the non-congested 

 sulistance is arranged in isolated, circular, and ramose patches, in the 

 centres of which the spaces and parts of the fissure are seen. This is an 

 extended degree of hepatic venous congestion ; it is " active congestion " of the 

 liver, and very commonly attends disease of the heart and lungs. 



These are instances of partial congestion ; but there is sometimes general 

 *tin of the organ. " In general congestion the whole liver is of a red 

 olour, but the central portions of the lobules are usually of a deeper hue 

 than the marginal portions.") 



DEVELOPMENT The liver of tho foetus is remarkable for its enormous 

 development. Its function commences early, for at birth the intestines are 

 filled with iiH'i-oiitnm, a product of the biliary secretion. A more detailed 

 description will be given when the general development of the fostus comes 

 to be studied. 



2. The Pancreas. 



This organ has the greatest resemblance to the salivary glands in its 

 struct in -i- and physical properties; and for this reason it has been named the 



t. It is situated in the sublumbar region, across the aorta and 

 rior vena cava, in front of the kidneys, and behind the liver and 

 stomach. Its weight is seventeen ounces. 



Ftirin and Relations. The pancreas is rather irregular and variable in 

 form, according to tho kind of animal. Flatt. n< <1 tioin above to below, 

 traversed obliquely from its inferior to its superior face by an opening for 

 the passage of the portal vein, and which is named tho pancreatic ring, this 

 gland is sometimes triangular, sometimes oblong, and curved on itself; it is 

 under tho latter form that wo will notice it. 



Its faces present tho lobulated aspect of salivary glands. Tho superior 



adheres by cellular tissue to the aorta, posterior vena cava, cu-liae trunk, 



solar plexus, splenic vessels, and the right kidney and supra-renal eai 



it is rov ( r. d by the peritoneum for a certain portion of its extent. The 



responds to tho base of tho erocum and the fourth portion of the 



