20 AN INTROD UCTION TO ENTOMOLOG Y 



Family Pauropodidce. — In members of this family the head is 

 not covered by the first tergal plate and the anal segment is not 

 covered by the sixth tergal plate. 



The best known representatives of this 

 family belong to the genus Pauropus (Fig. 

 22). This genus is widely distributed, represen- 

 tatives having been found in Europe and in both 

 North and South America. They are active, 

 measure about one twenty-fifth inch in length, 

 "s^^^ and are white. 



Family EiirypauropidcB. — The members of 



this family are characterized by the wide form 



of the body, which bears some resemblance to 



that of a sow-bug. The head is concealed by the 



first tergum of the body-region; and the anal 



segment, by the penultimate tergum. Our most 



familiar representative is Eiirypanropus spinosus 



^'l-^7.—Euryparcro- (pig_ ) ^^is, unlike Pauropus, is slow in its 

 pus spinosus (After ^ »^ ' ^ -r > 



Kenyon). movements. 



Class CHILOPODA 

 The Centipedes or Chilopods 



The members of this class are air-breathing arthropods in which the 

 head is distinct, and the remaining segments of the body form a continuous 

 region. The numerous pairs of legs are not grouped in double pairs, as 

 in the Diplopcda. The antennae are long and many-jointed. The 

 appendages of the first body-segment are jaw-like and function as organs 

 of offense, the poison-jaws. The opening of the reproductive organs is 

 in the next to the last segment of the body. 



The animals constituting the class Chilopoda or chilopods are 

 commonly known as centipedes. They vary to a considerable degree 

 in the form of the body, but in all except perhaps the sub-class 

 Notostigma the body-segments are distinct, not grouped in couples 

 as in the diplopods (Fig. 28). They are sharply distinguished from 

 the three preceding classes in the possession of poison-jaws and in 

 having the opening of the reproductive organs at the caudal end of 

 the body. 



The antennae are large, flexible, and consist of fourteen or more 

 segments. There are four pairs of jaws including the jaw-like 



