Branch Arthropoda 65 



THE LOCUST, OR GRASSHOPPER 



Collect as large specimens as you can find. Have the 

 dead grasshopper pierced with a pin or held with small 

 forceps so that the examination may be quickly and easily 

 made. Examine first with the naked eye, and then with a 

 hand lens or a dissecting microscope. 



I. — Take a general but careful view of the external feat- 



ures of the grasshopper. Lift the wings ; note their 

 number and place of attachment. Observe the num- 

 ber of pairs of legs and the location of the anterior 

 and posterior pairs. 



II. — There are three principal divisions of the body, — 

 head, thorax, and abdomen. Move the head gently 

 from side to side to see the line of division between it 

 and the rest of the body. Examine the long tapering 

 posterior part of the body : this is the abdomen. 

 Between it and the head lies the third great division 

 of the body, — the thorax. The anterior margin of the 

 thorax passes directly in front of the first pair of legs, 

 and the posterior boundary is just back of the third 

 pair of legs. Study the thorax carefully, remembering 

 that the two pairs of wings and the three pairs of legs 

 are all attached to it. 



III. — You have already noticed that the abdomen is 

 divided into segments, or somites, in a way some- 

 what similar to the abdomen of the lobster, but 

 with less freedom of motion. Look for a similar but 

 less marked series of divisions in the thorax. There 

 are really three segments in the thorax, each bearing 

 a pair of legs. See the first of these, — the prothorax, 

 — easily distinguished by the separation from the head 

 in front and from the rest of the thorax behind. The 



