. Text-book of normal histology: including an account of the development of the tissues and of the organs. channelscontaining corpuscles ; b, lumina of hepaticcylinders which correspond to bile-capil-laries ; c, pigment-cell. i8o NORMAL HISTOLOGY. Fig. 224. The of a distinct independent wall to the bile-capillarieshas been the subject of much conflicting testimony ; according to some, these vessels are with-out distinct walls of theirown, while other authoritiesregard the existence of a deli-cate special wall consisting of^-v^w Y=>.gf/Y . r/^ij;-jr ^^.,-_ - a homogeueous structur
. Text-book of normal histology: including an account of the development of the tissues and of the organs. channelscontaining corpuscles ; b, lumina of hepaticcylinders which correspond to bile-capil-laries ; c, pigment-cell. i8o NORMAL HISTOLOGY. Fig. 224. The of a distinct independent wall to the bile-capillarieshas been the subject of much conflicting testimony ; according to some, these vessels are with-out distinct walls of theirown, while other authoritiesregard the existence of a deli-cate special wall consisting of^-v^w Y=>.gf/Y . r/^ij;-jr ^^.,-_ - a homogeueous structureless\J^A C/^y^^T^V^YAXl^^^ membrane as established. ^ ^ ■ The presence of a distinct membranous wall seems ques-tionable ; when it is recalledthat the bile-capillaries reallyrepresent lumina of modi-fied tubular glands, thereseems to be no greater neces-sity for or probability of theexistence of a membrane tolimit the lumen of the bile-tubule than in the case of other glands. The direct transforma-tion of the secreting hepatic cells into the epithelium of the bile-duct at the margin of theFig. a^ Section of rabbits liver in which the bile-capillaries(i) have been injected and appear as dark lines betweenthe cells : c, blood-channels. W^^^^jg^jg lobule further opposes theassumption of such limitingmembrane, while examinationof livers in which the tubu-lar type of the acini is re-tained fails to show suchstructures within the luminaof the tubes. Emerging from the lobuleat the periphery to pass intothe adjacent interlobular con-nective tissue, the small bile-ducts empty into the largerones, which bear the branchesof the hepatic blood-vesselscompany. The interlobularbile-vessels gradually in-crease in size, owing to therepeated union of the smaller tubes, until the larger trunks unite toform the hepatic duct. While the walls of the smaller bile-ductsconsist of columnar epithelium strengthened by fibrous con-nective tissue mixed with elastic fibres, those of the large vesse
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Keywords: ., bookcentury1800, bookdecade1890, bookpublisherphiladelphiajblipp
