CHAPTER VIII. 
SOME INSECT ADAPTATIONS. 
Structure and Habits. Fig. 78 shows the parts of 
the hinder leg of a cockroach, an 
insect whose legs are well adapted 
for running. Comparing this leg 
with the corresponding legs of a 
grasshopper, we find the same 
parts present but modified for 
jumping. Looking at the legs 
of a mole-cricket, we find again 
the same parts, but.in this case 
altered for digging. Among the 
large water-bugs, which live by 
hunting, the legs are fitted for 
seizing and holding prey. In . 
some of these bugs, a portion of Fic. 78.—Leg ofa Cock- 
roach. a, coxa; 6 
the le g trochanter; <¢, femur; 
forms a d, tibia; ¢, tarsus. 
sheath into 
which another portion shuts 
like the blade of a 
pocket-knife when 
not in use (Fig. 80). 
Aquatic insects 
like the water-boat- 
x man (Notonecta) 
Fic. 79.—A Mole-cricket. and the large water- 
beetle (Ditycus) 
have legs made into powerful oars, which they are 
86 
