THE GRASSHOPPER. 55 



esophagus, is further comminuted and in part digested in 

 the crop and gizzard, is acted upon by the secretions of 

 the gastric caeca as it passes into the stomach, where diges- 

 tion is in the main completed. The digested food passes 

 out through the walls of the alimentary canal directly into 

 the blood, which bathes all the organs, and supplies them 

 with constructive material thus obtained from the food. 

 The Malpighian vessels reach out into the blood and 

 absorb from it noxious waste products of the body, which 

 they pass along out through the intestine, together with 

 the indigestible portion of the food. The blood gets 

 oxygen, necessary for both constructive and destructive 

 processes, by absorption of it (endosmosis) through the 

 tracheal walls. 



III. Nervous System. Remove carefully the alimen- 

 tary canal and its appendages, and look on the floor of the 

 body cavity for a double nerve cord extending the length 

 of the body, the two threads of it connecting on nearly 

 every segment with a double ganglion (a little, roundish 

 mass of nervous matter). Observe the nerve fibers that 

 radiate from each ganglion. These go to supply nerve 

 force to all parts of the body, and to supply nervous com- 

 munication between the parts. Trace the double nerve 

 cord to the head; then turn the head on one side, and pin 

 it firmly there through the front ; cut away the upper parts 

 until you discover a large ganglion situated above the be- 

 ginning of the esophagus, the cephalic ganglion (or brain) . 

 Observe that the double nerve cord begins here and passes 

 one thread around each side of the esophagus to the first 

 thoracic ganglion, and thence to the others of the system. 



Development. The development of the Carolina locust 

 may easily be traced, if the specimens of nymphs collected 

 alive are placed under a bell jar or glass dish, kept sup- 

 plied with fresh clover or lettuce leaves and water, and 



