Descriptive Zoology. 



or in vases where flowers have been standing for some 

 time, a film of scum is likely to appear. Just underneath 

 this film is a good place to look. Often the naked eye 

 may detect small white objects moving about. These are 

 paramecia. On examining some of the water with a low 

 power of the microscope, one discovers that these tiny 

 white specks are oval or elliptical, that they swim actively, 



Course of food vacuoles Contractile vacuole 



Contractile vaci 



Ventral view 



ANTERIOR MACRO- MICRO- MOUTH GULLET 

 END NUCLEUS NUCLEUS 



Oral groove 



Side view 



Mouth gullet Food ball 



Fir.. 171. PARAMECIUM, THE SLIPPER ANIMALCULE. 



usually with the same end foremost, and that when they 

 run against an obstruction they back off quickly. They 

 evidently have the power of moving and the sense of 

 touch. Looked at with a higher power, the shape may be 

 determined more definitely. They are somewhat flattened, 

 and one end is more pointed than the other. The dii 

 ference between the clear ectoplasm and the moi 

 granular endoplasm is more marked than in the amoel 



