40 ELEMENTARY BIOLOGY. [CHAP. 



In R. temporaria, the urinary bladder is larger 

 proportionately and more deeply lobed than in R. 

 esculenta. 



f. The spleen: a small red body lying in the middle 

 line, immediately in front and to your right of the 

 large intestine. 



g. The kidneys; two dark red lentil-shaped bodies, 

 seen, on displacing the intestine, lying close to- 

 gether in the middle line. 



h. The genital glands; immediately adjacent (ventral 



and external) to g. 



a. In the male. The testes: a pair of yellowish 

 bodies lying near the anterior ends of the 

 kidneys. 



ft. In the female. The ovaries; a pair of blackish 

 yellow bodies, coincident in position with, but 

 much more extensive than, a. Each is folded, 

 and seen to be composed of an immense number 

 of spherical ova. 



i. The fat masses (corpora adiposd) ; long filiform 

 deep-yellow processes attached to the anterior ends 

 of the genital glands. They are much the larger in 

 the male. 



/. The genital ducts; obvious in the female as highly 

 convoluted dead-white tubes (oviducts) lying imme- 

 diately beneath /?. (Those of the male may be 

 better studied later on.) 



k. The heart ; seen lying within a delicate sac (the 

 pericardiiuri) immediately in front of the liver. 



Slit open the pericardium. It will be found to 

 contain a fluid, (serous fluid} which bathes the en- 

 closed viscn? (heart). Examine the pleuro-peri- 



