458 



TEXTBOOK OF ZOOLOGY 



fin. The general shape of the body is fusiform or spindle-shaped 

 and hence offers little resistance to the water. In fact, the body 

 splits the water as it passes through it, and the water closes in on 

 the posterior slopes of the spindle shape to help force it forward. 



ESOPHAGUS 



UIVER 



6AL_U 



Bl_ADDER 



DUODENUM 



7t'!l\ CABDI AC 



STOMACH 

 PYLORUS 



:iT4-FUNDIC 



STOMACH 



SPl_EEN 



I_EUM 

 Al R 

 BUADDER 



Kr DNEV 



LARGE 

 INTESTINE 



TEST I S 



ANUS 

 ^BL-ADDER 

 I — VAS 



DEFERENS 



MESO- 



NEPHRIC 



DUCT 



UROGENI TA1_ 

 PAPIUL.A 



Fig. 249.- 



-Digestive system and other visceral organs of Ameiurus natalis. (Drawn 

 by Titus Evans from dissections by Rose Newman.) 



Digestive System and Digestion 



Except for some habits of a scavenger, the food of the bullhead is 

 similar to that of the yellow perch, which includes crayfishes, water 

 snails, insect larvae, as well as insects, and other small fish. The 

 dead bodies of almost any animal Avill be eaten by the bullhead. 

 The digestive system consists of the mouth, pharynx, esophagus, 

 stomach, intestines, and anus. The mouth is large and has teeth 



