296 THE DIGESTIVE ORGANS. 



oval nuclei it is more readily brought out with special stains, and 

 appears in such preparations in the form of structures to which the 

 name stellate cells has been given. In such cells blood corpuscles 

 and fragments of such were often found. The endothelium of these 

 capillaries possesses, therefore, a phagocytic function, taking up par- 

 ticles of foreign matter, blood-corpuscles, etc. 



The efferent ducts of the liver, the bile-ducts, are lined by col- 

 umnar epithelium, varying in height in direct proportion to the cal- 

 iber of the passage. The smallest ducts possess a low, the medium 

 sized a cubical, and the larger a columnar epithelium. The smaller 

 bile-ducts have no clearly defined external walls other than the 

 membrana propria ; the larger ones, on the other hand, possess a 

 connective-tissue sheath which may even present two layers in the 

 larger passages. Unstriped muscular fibers occur in the large 



L/ 



Fig. 237. From preparation from the liver of a rabbit, showing the so-called stellate 

 cells of Kupffer : a, Stellate cells ; b, liver cells. 



ducts, and also small mucous glands. The gall-bladder consists 

 of a mucous, fibro-muscular, and, where covered by the peritoneum, 

 of a subserous and serous coats, as has recently been shown 

 by Sudler, whose account is here followed. 



The mucous coat is covered by a single layer of columnar epi- 

 thelium, with nuclei situated in the basal portions of the cells. The 

 epithelial cells rest on a poorly developed muscularis mucosae. The 

 mucosa presents folds, covering ridges of connective tissue of the 

 fibro-muscular layer, and contains small lymph-nodules, and a 

 varying number of small mucous glands. The fibro-muscular 

 layer consists of interlacing bands of nonstriated muscle and 

 fibrous connective tissue, and is not arranged in distinct layers. 

 The subserous and serous coats present the same appearance as in 

 other regions of the peritoneum. The artery or arteries going to 

 the gall-bladder divide into branches which form capillaries in the 

 mucosa under the epithelium; these are most numerous in the 



