286 ELEMENTARY ENTOMOLOGY 



SECTION VIII. COMPARISON OF INSECTS AND ARACHNIDA 

 (TYPES, SPIDER (Argiope) AND LOCUST) 



Material. When possible, the ladder-spider should be collected for this work, 

 as it is large, brilliantly colored, and can usually be collected in large numbers 

 in the fall. 



Exercise 23. Write out a careful comparison of the following parts : 



1 . The covering of the body and segmentation. 



2. The general divisions of the body. 



3. The eyes (located on the anterior portion of the cephalothorax), their 

 number, arrangement, etc. 



4. The mouth-parts, consisting of the mandibles, with terminal fang, maxillae, 

 hypopharynx, and a rudimentary labium. 



5. The legs, number, number of segments, etc. 



6. The abdomen, including the following structures : 



a. The opening of the book-lungs, which lie on either side of the me- 



dian line at the anterior end of the abdomen and are respiratory 

 in function. 



b. The genital opening, situated in the female on a prominent median 



tubercle located between the book-lungs. 



c. The spinnerets, consisting of six papillae at the posterior end of the 



body. 



Exercise 24. Make a drawing of a dorsal view of the spider. 

 Exercise 25. Make a drawing of the mandibles and maxillae of the spider. 



