124 PISCES (the fish) 



(b) Shape? 



(c) Color? 



(d) Number? 



(e) Use? 



(7) The Intestines. 



(a) Are they straight or coiled? 



(b) If coiled, unravel them and compare their length 



with that of the whole fish. 



(8) The Spleen. 



(a) Location? 



(b) Use? 



2. The Swimming Bladder — dorsal to the intestines. Use? 



3. The Excretory Organs — the kidneys. 



(1) Location? 



(2) Use? 



4. The Circulatory Organs.^ 



(1) The Heart. (Note its pericardial cavity.) 



(a) Sinus venosus. Use? 



(b) Auricle. Use? 



(c) Ventricle. Use? 



(d) Bulbous arteriosus. Use? 



(2) The Arteries. Traced to what organs? Function? 



(3) The Veins. Traced to what organs? Function? 



(4) Use of pericardial cavity? 



(5) Make a diagram showing the principal parts of the cir-. 



culatory system. 



5. The Nervous System. 



(1) Dissect away the muscles and bones along the dorsal 



side, and expose the brain,^ spinal cord, and main 

 nerves. 



(2) Special Senses. 



(a) How many senses has the fish? 



(b) Name them. 



(c) Name those of man. 



^See Fig. 160, "Principles of Economic Zoology." 

 2 See Fig. 161, " Principles of Economic Zoology." 



