LOCUSTS AND GRASSHOPPERS. 95 



of locusts and grasshoppers. Below the antennae in front is the 

 " clypeus," or visor (Fig. 99, C), and to the clypeus is attached a 

 loose flap called the upper lip (labrum), which may be readily moved 

 up and down. 



How these grasshoppers take their food is not commonly under- 

 stood; but a little close observation of the parts of the mouth will 

 teach us. They consist of a pair of true jaws called " mandibles;" 

 and of a pair of accessory jaws called maxillae, and of the under lip 

 or labium. 



The jaws are black, horny, and toothed along the free or cutting edge. 

 They work laterally, and are well adapted for catting off bits of leaves 

 and stalks of grass, passing through the leaf somewhat like a circular 

 saw. One can easily watch the process. 



But the food must be tasted and arranged in favorable positions and 

 held between the jaws. In doing this the maxillae arc of service. If 

 a maxilla is removed and examined with the microscope, we shall see 

 that it is divided into three parts, an inner, middle, and outer divi- 

 sion. The inner is like a slender jaw, with sharp, teeth-like hooks; 

 these serve to hold the food while it is being cut or ground to pieces 

 by the millstone-like jaws. The middle division is somewhat spoon- 

 shaped; its special use is not well known. The outer division is a 

 feeler (palpus), and consists of five joints. The sense of taste, and per- 

 haps smell, probably exist in the feelers of some insects. 



The under lip forms the lower side of the mouth, and is a movable 

 flap, which supports another pair of tasters or feelers, which are, how- 

 ever, only three- jointed. We thus see that the mouth-parts of the in- 

 sect are fewer in number and simpler in form than those of the lob- 

 ster. 



Now, one may like to know how insects hear and where the ears are 

 situated. Strangely enough, they are not in the head or near it, but in 

 locusts they are placed on the first ring of the hind body, where they 

 form a sac, as is to be seen in Fig. 98. One can easily find the two 

 auditory sacs by lifting up the wings and looking for them at the 

 base of the hind body. In the green grasshoppers and crickets the 

 ears are situated in the fore-legs. 



Having ears to hear, locusts,, grasshoppers, and crickets 

 are also very musical. One may sometimes see the red-legged 

 locust standing on the ground and rubbing one leg against 

 the folded wing, and a shrill chirruping noise may be heard. 

 The noise is made by a row of dull spines on the inside of 

 the femur, forming a rude file which rasps the wing. Cer- 

 tain grasshoppers, as the katydid and the crickets,, have on 



