6 A MANUAL OF ZOOLOGY 



stant? Compare with the amoeba. Look for a tube, the 

 oesophagus, leading from the mouth to the interior. Are 

 there any cilia here? What seems to. be their function? 

 During the study of a specimen it may be seen to eject 

 waste material through an opening in the body wall, the 

 anus. Is its position constant? When is it seen? Note 

 the food particles filling into the spaces as the animal 

 gathers food. Are these food vacuoles constant in number 

 and size in all specimens? Make a large drawing showing 

 all structures of the paramoecium. 



PHYSIOLOG-Y— What are the motions of the body as 

 a whole? What are the organs of locomotion? Are all the 

 motions of the body caused by these organs? Study the 

 motions of the cilia. Are they all used for the same pur- 

 pose? Apply a drop of 1 per cent acetic acid and note the 

 effect on the trichocysts. FrOm this eflfect, what would be 

 considered the function of the trichocysts? Study the 

 contractile vacuole in a live specimen for several minutes 

 and note any peculiarities in the movements of this organ. 

 How does the motion of the food vacuoles cdmpare with 

 the motion in the contractile vacuole? How does th« 

 paramoecium take its food? Compare with the amoeba. 

 Note the formation of the food balls in the food vacuoles. 

 As they move about the body note any change in the size 

 of the balls. How is this change accounted for? Stain 

 with dilute iodine and ascertain what the paramoecium 

 eats. Iodine stains starch blue and >albumihous substances 

 brown. Feed some live specimens some ground carmine 

 as in the amoeba. Is there any concert of action on the 

 part of the animal? Can the next movement be anticipated 

 In observing him? Is there anything about the paramoe- 

 cium that would lead one to think that it has any special 

 senses? Darken one side of a dish containing large num- 

 bers of the animals and I'eave it four or five hours in a 

 light place. Examine with a hand lens and find'which side 

 of the dish has the more of them. The paramoecium has 

 two methods of reproduction by fission and by conjugation. 

 Different specimens may be found representing each of 

 these methods. Watch the process through in either case 

 and observe the method In detail. Make a drawing on a 

 large scale of the animal. 



