3 2 Practical Zoology. 



habit of coiling its body into a spiral when disturbed. This is a 

 milliped. 



1. How many segments has the body? 



2. How many appendages has each segment? 



3. Make a drawing of the thousand legs. 



4. What are the chief differences between this animal and 

 insects? 



Another common form of thousand legs is that called centiped. 

 It is, when full grown, about an inch long, with a broad, flat head, 

 a brown, shiny back, the segments being generally about the same 

 size, with one pair of jointed appendages to each segment. The 

 antennae are many-jointed. It is found under boards and about 

 rubbish and manure heaps, where it feeds on insects and earth- 

 worms. It usually runs actively when uncovered. 



1. Examine the jaws and mouth parts carefully; how many 

 pairs of jaws are there? 



2. With a lens examine the legs. How many are there? 



3. What kind of eyes are there? How many, and how placed? 



4. Arrange the legs so they can be distinctly seen, and make a 

 drawing as seen from above. 



5. Make an enlarged drawing of the mouth parts as seen from 

 below. 



6. What are the differences between this form and the thou- 

 sand legs mentioned above? 



7. In what are the two alike? Both belong to the class Myria- 

 poda. Carefully compare them with the insects, and make a list 

 of points common to insects and myriapods ; also a list of the 

 characters which insects have and the myriapods do not have; 

 and a list of points peculiar to myriapods. 



