18 PRACTICAL ZOOLOGY. 



5. A pair of strong jaws, the mandibles, often very large, 

 and projecting forward as pinchers, or " horns." How 

 do they move ? 



6. Back of these are two small jaws, the maxillae, bear- 

 ing a pair of jointed appendages, the maxillary palpi. 



7. Back of (posterior to) the maxillary palpi is another 

 pair of similar appendages, the labial palpi. 



8. The part of the body back of the head is the protho- 

 rax. Why not call it the thorax ? 



9. Pry up the hard outer wings. How do they meet 

 each other? The outer wings are called the wing 

 covers, or elytra. In what direction does the beetle 

 move the elytra in raising them ? How are they held 

 during flight? Do they rise vertically? 



10. How are the inner wings folded? Compare the inner 

 and outer wings in length and size. Cut a piece of 

 paper of the same shape as the inner wing, and fold it 

 as the inner wing is folded. How does the beetle 

 perform the act of folding the inner wings? Capture 

 live beetles and watch this process. 



11. Make a drawing of the back, with the wings closed ; 

 another drawing, with the wings fully expanded, as in 

 flight. 



12. Count the segments of the legs. Examine each seg- 

 ment closely. Seize the foot of one of the hind legs 

 with the forceps, and pull it about in all directions, 

 to see how many joints the leg has, and what motions 

 are allowed by each joint. The segment nearest to the 

 body is the coxa. Then come in order, trochanter, 

 femur, tibia, and tarsus (foot). 



13. What marks the line of division between the thorax 

 and abdomen ? 



