42 LABORATORY DIRECTIONS 



8. Note the streaming of granules in the endoplasm. Direc- 

 tion? Distinguish the spherical food and zvater vacuoles, the 

 minute structural granules of the endoplasm, and the small 

 crystals. 



9. Describe the course of the oral groove. On what sur- 

 face of the animal is it located? The groove continues at its 

 posterior end into the gullet. Describe the course of the gullet. 

 Is it lined with cilia? 



Solid waste material which accumulates in the body is dis- 

 charged through a special opening called the anus. Ordinarily 

 this is not observable except when waste matter is being given 

 off. There was neither mouth nor anus in Amoeba. Why are 

 they necessary in Paramecium? Notes required. 



10. CONTRACTILE VACUOLES. How many? Position? Is 

 it definite? In which body layer? Radiating canals. When best 

 seen? How many? Do they always communicate with the con- 

 tractile vacuoles? How are vacuoles filled? How and where 

 do they empty? Best determined by examination from right or 

 left side. Accurately time 5 pulsations. Warm and time. Notes 

 or table required. 



it. NUCLEI. Division of labor is accompnaied by a special- 

 ization of the nuclear material in the Ciliates. Instead of a single 

 nuclear mass there are two nuclei in each cell. The larger of 

 these, called the macronucleus, seems to have control of the ordi- 

 nary bodily functions, while the micronucleus is concerned chiefly 

 in the reproductive process. These nuclei are not observable in 

 the living animal. At the demonstration table examine stained 

 specimens. By use of the ocular micrometer measure the length 

 of the entire animal, the macronucleus, and micronucleus. Use 

 these measurements to insure correct proportions in drawing 

 asked for in next paragraph. 



12. Make a large drawing, 150 mm. long, of a living Para- 

 mecium, side view, locating and labeling various structures. Show 

 structure carefully in part of drawing i cm. back from the an- 

 terior end of the body. In remainder of body show division be- 



