(>4 Anatomy and Physioloyy. 



We do not therefore share the opinion of MM. Dujardin 

 and Verger, who suppose that the blood circulates freely 

 through the hepatic tissue, without being confined in special 

 vessels. We are equally obliged to differ from Guillot, who 

 supposes that the blood circulates in the liver through non- 

 membranous canals. All microscopic observations are opposed 

 to these opinions, and an attentive examination of the hepatic 

 tissue demonstrates their inaccuracy. 



We have hitherto spoken of masses of cellules surrounded 

 by capillaries ; we have stilj to make out the termination 

 of the biliary canals : it is an extremely difficult subject, and 

 one which probably still requires many new researches. To 

 elucidate it, we have thought it useful to study first the liver 

 of inferior animals, and we have chosen with this view the 

 crustacese, and especially the crawfish. 



In these animals, as is known, the liver is composed of 

 isolated lobes, of a tube shape. Each of these tubes, when 

 placed in a drop of water, without being covered by another 

 glass, and examined by a magnifying power of 150 to 200 

 diameters, is composed, according to our observations, of a 

 very fine exterior membrane, of a parenchyma, and an interior 

 cavity filled with bile. The parenchyma is thickest at the 

 free end of the tube, and gets thinner towards the other 

 extremity. It is composed of cellules in various stages of 

 development. The internal cavity or biliary canalicle is filled 

 with little drops of fat, and of a white amorphous substance, 

 which we have had occasion several times to allude to. 

 These drops sometimes accidentally enclose granules, or even 

 hepatic cellules, which gives them the appearance of true 

 cellules. By degrees they become opaque, and one, two, or 

 even more transparent little drops of a brownish-red tint form 

 in their interior. 



These researches had long been completed when we re- 

 ceived several Memoirs on the same subject, which appear to 

 us to contain inaccurate results. Thus the parenchyma of 



