THE ORGANS OF DIGESTION". 



265 



(man, anthropoids) differs widely in form and lobulation from 

 that of mammals generally, but Professor Arthur Thomson has 

 shown that traces of the fissures and lobes of the typical mam- 

 malian liver can be seen in the human organ. The liver of a 

 dog or dog-like ape consists of three main lobes — right, middle 

 and left, and two accessory lobes- — the caudate and Spigelian 

 (Fig. 214). In man the right and middle lobes have fused, but 

 traces of the fissure which separates them (the right lateral 

 fissure) are frequently to be seen in the liver of the newly-born 

 child (Fig. 215). The caudate lobe has been reduced in man to 

 a vestige, but in the third month foetus it is of considerable size 

 (Fig. 215). It projects from the liver at the upper boundary 

 of the foramen of Winslow; in many animals it rivals the right 

 lobe in size. The caudate fissure separates the caudate from the 

 right lobe, and a trace of this fissure is very frequently to be seen 

 in the human liver (Fig. 215). 



Spigelian eaud _ , obe 



left iat. lobe 

 lig. tere. 



caud. fls. 

 right Iat lobe 



-right Iat. fissure 



gl. bladder 



middle lobe 



Fig 215 —The lower surface of the Liver of a human foetus during the 3rd month, 

 showing Vestiges of Fissures and Lobes of the typical mammalian Liver. 



After the second month the growth of the right lobe is more 

 rapid than that of the left. At birth the left lobe still touches 

 the spleen, a relationship more frequently retained in women 

 than in men. Eiedel's lobe is a linguiform prolongation of 

 the right lobe below the 10th right costal cartilage caused by 

 compression. 



Gall Bladder.— It is developed from the common stalk 

 (common bile duct) as a diverticulum in the second month (Fig. 



