ELEMENTARY BIOLOGY. [CHAP. 



d. The liver: a great brown two-lobed mass; its 

 left lobe the larger and subdivided into two. 



e. The lungs: \hz posterior ends of these maybe 

 seen as sacculated pouches, one on each side of 

 the liver, but they are frequently not visible 

 until the latter organ has been removed. 



/ The stomach: a small portion of this is seen pro- 

 jecting beyond the lower left border of the 

 liver. 



g. The intestine: a convoluted tube, continuous with 

 the stomach, and slung by a delicate membrane, 

 the mesentery: posteriorly the intestine ends in a 

 dilated portion (rectum) which runs into the 

 pelvis. 



h. The urinary bladder: a thin-walled bilobed sac 

 (which may or may not be distended) appear- 

 ing just in front of the pelvis. 



i. The fat masses: long slender yellow processes 

 appearing on each side of the liver. 



In R. temporaria, the urinary bladder is much 

 more deeply lobed and also much larger propor- 

 tionately, than in R. esculenta. 



The liver. 



a. Study its form more closely. (6. d.) 



b. Raise its lower border; between its two lobes 

 will be seen a small greenish sac, the gall-bladder. 



c. Carefully cut away the liver, except its deepest 

 part, close to the venous sinus. 



d. Tease out a bit of liver in 075$ sodic chloride 

 solution and examine with \ obj. 



