THE GRASSHOPPER AND OTHER ORTHOPTERA 7 



intestine which is narrow and more or less coiled. The 

 latter leads to the terminal portion of the alimentary 

 canal, the rectum, which opens through the last segment 

 of the body. The food as it passes down the alimentary 

 canal is acted on by the saliva, the secretion of the gastric 

 cceca, and other fluids formed by the walls of the stomach 

 whereby it undergoes a process of digestion after which 

 the soluble materials are absorbed through the walls of 

 the alimentary canal, especially the stomach and intestine, 

 and carried to various parts of the body. The undigested 

 residue is expelled through the rectum. 



FIG. 5. Diagram of the internal organs of a grasshopper, c, crop; 

 gc, gastric coeca; vn, ventriculus, il, ileum or anterior part of the intestine; 

 co, colon, r, rectum; e, eye; g, g, ganglia; nc, nerve cord; sg, salivary glands; 

 mt, Malpighian tubules; ov, ovary; od, oviduct; op, ovipositor. (Modified 

 from Brooks.) 



The absorbed food materials are carried to different 

 organs by means of the blood which is not red as in our- 

 selves, but nearly colorless. The organ for propelling the 

 blood is the heart, an organ very different in appearance 

 and position from our own heart, as it consists of a long 

 tube lying along the upper part of the abdomen. It is 

 closed behind but open in front, and is perforated by 

 several pairs of openings along the sides. Blood enters 

 through these lateral openings and is prevented from 

 flowing back by valves. The heart beats or contracts from 

 behind forward so that the blood which is drawn in through 



