132 WORMS 



Can it swim? How? Take it out of the water. Can it 

 move? How? Can it live out of water very long? 



(3) Notice the sticker at the anterior end of the body. 

 Look in this sucker for the mouth. What is the sucker 

 used for? Has it another sucker? What is it used for? 

 Do you find an anus? 



(4) This animal is called a blood sucker. Why? 



(5) Draw the entire animal, ventral view. In what 

 respects is it like the earthworm? How does it differ 

 externally? Draw (X2). 



A PLANARIAN WORM 



Planaria are usually abundant in fresh water ponds or 

 lagoons at all times of the year. They may be found crawl- 

 ing over water plants such as philotria, chara, pondscum, 

 etc. Pull these plants up with a hook and place them in 

 jars in the laboratory. Soon the sides and the top of the 

 vessel will be covered with planarian worms. 



(2) Examine a living animal in water under compound 

 microscope. Note its color. Is the color the same on both 

 sides ? Why ? Is this of any advantage to the animal ? Has 

 it an anterior and a posterior end? A dorsal and a ventral 

 side? Describe fully its shape. Is its shape adapted to its 

 mode of life? How? Look on the dorsal front end for 

 eyes. How many ? Color ? Examine the ventral side as the 

 worm crawls over the glass vessel. Do you find a mouth? 

 Where is it situated? How does the worm move? How 

 does it hold fast to an object? Notice its slimy feel. Make 

 a sketch (X4). 



