:90 



ANATOMY OF VERTEBRATES. 



375 



distribution through the portal canal, fig. 373,^, where the minute 

 branches form i vaginal plexuses,' sending off interlobular branches 

 which terminate in the lobule by a capillary plexus communicat- 

 ing and localised with the portal one. The meshes of the radially 

 arranged plexuses, fig. 375, are occupied by organites which subsist 

 by endosmotic intussusception and assimilation of blood-elements, 

 modify them by interchange of other elementary combinations, 

 then perish by rupture or solution of their walls. These bodies, 

 called i hepatic cells,' much exceed in size the monads of infusoria, 1 

 being about xoVo^h mcn m diameter; but, like them, they have 

 a hyaline granulated nucleus, which contrasts by its refractive 

 brightness with the tawny yellow of the minuter granules of the 

 main contents of the cell, in which also float oil-globules. These 

 contents, exuded or set free, fill the intervals of the ( nucleated 

 cells,' and form the s bile,' or brief equivalent of ' bile vesicles 

 without proper walls.' 2 When an epithelium is discernible, sepa- 

 rating them from the capillaries, 3 the bile-ducts may be said to 

 commence. The inductive figure given by Kiernan of the intra- 

 lobular or initial bile-conduits, fig. 375, receives support from the 

 recent careful researches of Hering in the liver of the rabbit : 



he describes them as form- 

 ing a plexus with polygonal 

 meshes 4 from which the 

 canals are continued to form 

 the interlobular ducts, a, a ; 

 from these are continued the 

 ' vaginal branches,' fig. 373, 

 h, which progressively unite 

 to form the hepatic ducts. 

 These, in Man, emerge, two 

 in number, at the portal fis- 

 sure : in more divided livers 

 the liberated ducts are more numerous ; but all unite, as a rule in 

 Mammals, into one trunk, which, in those having a gall-bladder, 

 joins the cystic duct to form the ( ductus communis choledochus.' 

 This duct, fig. 376, a, penetrates the duodenum distinctly from 

 the pancreatic duct, b, both run obliquely between the several 



1 Such, e.g. as the Monas atomus, ^^h line in diameter. 

 ' Ein Gallencapillarystem ohne eigene Wandung.' clix". p. 241. 

 The 'when' or ' where' such ' epithelial walls' are gained, forming a beginning 

 of proper conduits for carrying off the bile from the interspaces of the formative cells, 

 may long be debateable ground with Micrographers ; as now between Beale, Budge, 

 and Hering. clix". p. 241. 



4 'Ein Netz mit polygonalen Maschen,' cox'', p. 241. Kiernan obtained a viYw 

 of anastomosing biliary ducts in part of a lateral ligament of the human liver; clvii". 

 p. 769, pi. xxiv. fig. 4. 



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Lobular biliary plexus, clvii." 



