102 ANTHROPOLOGY. 



of the left fissure of the liver, there to divide into right and left branches, 

 which in the liver become subdivided into smaller branches divisible into 

 three orders : vaginai^ interlobular, and lobular. The lobular branches con- 

 stitute the ultimate ramifications, entering and forming a plexus in each 

 lobule of the liver ; they are then continued into the intralobular veins, 

 which unite in the sublobular, these combining to form the hepatic trunks of 

 the hepatic veins which pour their blood into the inferior vena cava. In 

 the lobules, the venous blood is depurated by the secretion of the bile, 

 which pours into the hepatic ducts. The object of the hepatic artery is pro- 

 bably nutritive, and not secreting as formerly supposed. 



PI. 133, fig. 5', liver; ", gall-bladder and duct ; ', hepatic artery ; *, infe- 

 rior vena cava; *'•*', head of the pancreas ; ^'*, the two posterior sections of 

 the duodenum ; "''-''^ folds of the small intestines ; ', coecum and ascending 

 colon ; ", descending colon and rectum ; *, vspleen ; '°, stomach turned back; 

 "' ", veins of the jejunum and ileum ; ", right vein of the ileum ; ", superior 

 mesenteric vein ; "' ", splenic vein ; '^, lesser mesenteric vein ; '°, left plexal 

 vein of the stomach; ", left coronary vein of the stomach ; "•", trunk of 

 the vena porta ; ", umbilical vein. 



5. The Lymphatics. 



Absorption, so necessary to nutrition, is effected by means of minute 

 vessels termed absorbents, and the small reddish bodies termed absorbent 

 or conglobate lymphatic glands, through which the absorbents pass. The 

 absorbents are divided into two classes, named lymphatics and lacteals. 

 The lacteals are found only in the abdomen, and are so called from the 

 milky appearance of the chyle which they absorb from the intestinal villi, 

 and which is conveyed by their trunk, the thoracic duct, into the general 

 circulation. The lymphatics are so named from the clear fluid or lymph 

 they contain ; they are distributed through all parts of the body, and their 

 office is to absorb in every tissue all matters that have become effete or 

 useless : these, being first reduced to a state of solution, are conveyed into 

 the general circulation, either to be discharged from the system by some of 

 the excretory organs, or to undergo certain changes fitting them again foi* 

 the purposes of the animal economy. The lymphatics are arranged, like 

 veins, into superficial and deep ; the former accompany the subcutaneous 

 veins, the latter the deep-seated vessels ; they run very much parallel to 

 each other, often bifurcate, and either soon reunite or join similar adjacent 

 branches : as they approach any of the glands they converge, each divides 

 into two, which inclose its extremity, and soon enter through its surfaces; 

 tliese are the vasa inferentia. Within the gland they subdivide and inos- 

 culate so as to form an inextricable plexus; from this, branches again issue 

 and leave the gland by the opposite end ; these are the vasa efferentia, and 

 are larger, but fewer, than the vasa inferentia. All absorbents pass 

 through one gland at least, and some through more, before they empty into 

 the vente innominatae. The structure of the absorbents is very similar to 

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