THE GRASSHOPPER. 7 



4. In the anterior part of the abdomen a mass of yellow 

 eggs is usually to be found ; this mass may be easily 

 separated into two parts, right and left, from each of 

 which a tube, oviduct, leads to an opening between 

 the parts of the ovipositor. 



5. Under the eggs is the dark intestine, running length- 

 wise. 



6. Remove the roof of the thorax ; more air sacs should 

 be found here. In the upper part of the thorax are 

 the white muscles which move the wings. Remov- 

 ing these muscles exposes more of the digestive tube ; 

 as the food is swallowed, it passes upward in a brown 

 tube, which soon turns backward into the thorax ; in 

 the prothorax, the enlargement is the crop, in which 

 is produced the dark liquid which the grasshopper 

 ejects from the mouth when held captive. The crop 

 may be removed, washed, split open and examined 

 under the microscope with a half-inch objective to show 

 the rows of hooked teeth with which it is provided. 

 .A little further back the digestive tube is surrounded 

 by a set of double cone-shape pouches, which extend 

 parallel with the main channel of the digestive tube. 

 These are the gastric caeca. Behind them is the 

 stomach, followed by the intestine. The products of 

 digestion pass through the coatings of the digestive 

 canal, and mingle with the currents of blood which 

 pass along the ventral and lateral parts of the body. 



7. The colorless blood enters the heart through holes 

 along its sides; blood is sent from the heart into the 

 veins of the wings. These veins are hollow tubes, 

 and though they convey blood, are very different 

 from the veins in our bodies. Air tubes run along 



