SLIME SLUGS, MYRIAPODS AND INSECTS 145 



parts of which two are feelers, or labial palpi, much like the 

 maxillary palpi and also provided with taste buds at their 

 tips. With the strong, hard-toothed jaws the grasshopper 

 can bite off and crush not alone bits of soft green leaves but bits 

 of plant stalks and even woody stems. The biting type of 

 mouth-parts like the grasshopper's, although with many slight 

 differences in the make-up of the various parts, is possessed 

 by the cockroaches, crickets and katydids which belong to the 

 same insect order as the grasshoppers, and also by the beetles, 

 the dragon-flies, the white ants, and various other less familiar 

 insects. All such insects bite off and chew more or less solid 

 substances. 



Mouth -parts of Cicadas, Squash-bugs, etc. Cicadas, 

 squash-bugs, bedbugs, and many other sap-sucking and blood- 



FIG. 61. Head and prothorax of water-bug, Serphus dilatatus. Show- 

 ing the piercing beak and the first pair of legs which are fitted for grasping. 

 (About natural size.) 



sucking insects that belong in the same order with them 

 have a slender, sharp-pointed, more or less firm piercing beak 

 which is composed of a tubular sheath inside of which are 

 four sharp needle-like pieces which can project out of the 

 end of the sheath and be worked back and forth so as to 

 lacerate plant or animal tissue and thus cause a flow of sap or 

 blood which is sucked up the sheath into the mouth. The 



