Find the =ears= on the front wall of the _first abdominal ring_ (Fig. 107). They may be seen by slightly pressing the abdomen so as to widen the chink between it and the thorax. The ears are merely glistening, transparent _membranes_, oval in form. A _nerve_ leads from the inner surface of each membrane. State any advantage or disadvantage in having the ears located where they are. [Illustration: FIG. 108.—GRASSHOPPER LAYING EGGS. (Riley.) ] =Ovipositor.=—If the specimen is a female, it has an egg-placer or ovipositor, consisting of _four blunt projections_ at the end of the abdomen (Fig. 107). If it is a male, there are two appendages above the end of the abdomen, and smaller than the parts of the ovipositor. Females are larger and more abundant than males. In laying the eggs, the four blunt points are brought tightly together and then forced into the ground and opened (Fig. 108). By repeating this, the grasshopper makes a pit almost as deep as the abdomen is long. The eggs are laid in the bottom of the pit. =Draw= a side view of the grasshopper. =Thorax.=—This, the middle portion of the body, consists of _three segments_ or rings (Fig. 107). Is the division between the rings most apparent above or below? Which two of the three rings are more closely united? The front ring of the thorax is called _prothorax_. Is it larger above or below? Does it look more like a collar or a cape? (Fig. 106.) A spiracle is found on the second ring (_mesothorax_, or middle thorax) just above the second pair of legs. There is another in the soft skin between the prothorax and the mesothorax just under the large cape or collar. The last ring of the thorax is called the _metathorax_ (rear thorax). How many =legs= are attached to each ring of the thorax? Can a grasshopper walk? Run? Climb? Jump? Fly? Do any of the legs set forward? (See Fig. 106.) Outward? Backward? Can you give reasons for the position of each pair? (Suggestion: What is the use of each pair?) If an organ is modified so that it is suited to serve some particular purpose or function, it is said to be _specialized_. Are any of the legs specialized so that they serve for a purpose different from that of the other legs? [Illustration: FIG. 109.—HOW A GRASSHOPPER WALKS. ] [Illustration: FIG. 110.—HOW A SPIDER WALKS. ] The leg of a grasshopper (as of all insects) is said to have _five parts_, all the small parts after the first four parts being counted as one part and called the foot. Are all the legs similar, that is, do the short and the long joints in all come in the same order? Numbered in order from the body, which joint of the leg is the largest,—the first, second, third, or fourth? Which joint is the shortest? The slenderest? Which joint has a number of sharp points or spines on it? Find by experiment whether these spines are of use in walking (Fig. 106). Jumping? Climbing? In what order are the legs used in walking? How many legs support the body at each step?