. Elements of Comparative Anatomy. 564 COMPARATIVE ANATOMY. and othei' processes, wliile tliey give rise to tlie bile-ducts by tbe formation of intercellular passages, wliicb run in the axes of_ tlie epitbelial chords. The hepatic lobes, which are formed on_ either side, fuse with one another into a single organ. The two primitive diverticula, after they have formed the bile-ducts in the parenchyma of the liver, and have been continued iuto the network of cellular chords, form the efferent ducts of the liver. The liver, which is thus differentiated from the enteron, forms a compact, and ordina
. Elements of Comparative Anatomy. 564 COMPARATIVE ANATOMY. and othei' processes, wliile tliey give rise to tlie bile-ducts by tbe formation of intercellular passages, wliicb run in the axes of_ tlie epitbelial chords. The hepatic lobes, which are formed on_ either side, fuse with one another into a single organ. The two primitive diverticula, after they have formed the bile-ducts in the parenchyma of the liver, and have been continued iuto the network of cellular chords, form the efferent ducts of the liver. The liver, which is thus differentiated from the enteron, forms a compact, and ordinarily, very large organ; it is embedded in a fold of the peritoneum, which extends from the anterior portion of the enteric tube to the anterior wall of the abdomen. In Fishes, the liver generally forms a single, undivided mass, but sometimes it consists of two, or more lobes. There are two large portions in the Amphibia; it is gene- rally simple in the Ophidii, and is merely notched at the margin in the Saurii; in the Crocodilini and Chelonii it is again divided into two lobes, which in the latter are widely sepa- rated from one another, and united by a slender transverse bridge. Ordi- narily two lobes are, sometimes more, sometimes less, indicated in the Mam- malia. In the Carnivora, Rodeutia, some Marsupialia, Simile, and others we find, indeed, multilobate forms, but these may be referred to two larger primary lobes. There are various modifications in the character of the efferent ducts (ductus hepato-enterici) in relation to their primitively double character; for either the first condition persists, or the two ducts are gi'adually fused to- gether, that is to say, the diverticulum of the enteron is converted into a single duct, or, lastly, the primitive ducts are atrophied, and secondary canals are converted into efferent ducts; in this case there is a large number of ducts (in the Saurii and Ophidii). A unilatei-al C96cal diverti- culum, the gall-bladder (,/) is pl
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Keywords: ., bo, bookcentury1800, bookdecade1870, bookpublisherlondonmacmillan
