The Grasshopper 339 



as the hypopharynx, at the base of which a tube opens from the several 

 salivary glands. The epipharynx is the organ of taste, and is located on 

 the slightly convex surface of the inner side of the labium. 



The continuation of the mouth leads into the short curved oesopha- 

 gus which in turn leads to the large ingluvies ( ) or 

 crop. Here are seen various rows of spine-like teeth. The proventric- 

 ulus, or gizzard ( ), follows. This is a very small 

 organ also furnished with spines ; it empties into the large, thin-walled 

 ventriculus or stomach. Six tubular gastric caeca, or blind sacs, are 

 attached to the anterior end of the stomach. Posterior to the stomach 

 the alimentary canal forms the intestine which is divided into three 

 portions: the ileum ( ), rather slender, with 

 longitudinal ridges on the inside (the infolding ridges increase the 

 absorbing surface) ; the colon, smaller than the ileum and possessing a 

 smooth lining; and the rectum, which has six longitudinal rectal glands 

 of unknown function. 



The food of the red-legged locust, which feeds quite freely by day 

 (unlike the crickets and katydids which are more active at night), con- 

 sists of grass and little drops of dew. The pads at the tips of the legs, 

 and the claws, enable the animal to climb stalks of all kinds very readily. 

 This eating of dew rather than drinking at pools of water, has given us 

 the idea that there is something about standing-water that is fatal to 

 the grasshopper. That this idea is correct is evidenced by the fact that 

 grasshoppers kept in captivity must be sprinkled with drops of water or 

 they usually perish. 



As food is taken into the mouth, the salivary glands pour their 

 secretions forth to assist in preparing it for reception in the crop to 

 which it passes through the oesophagus. Here it is mixed with a 

 molasses-colored digestive fluid. It then passes on to be ground up 

 still further by the spinous processes in the muscular gizzard. The 

 various gastric caeca, each of which has an anterior and a posterior 

 pocket, increase the stomach space. 



Once the food has passed through the stage just mentioned, it be- 

 comes part of the blood of the grasshopper. This it does by being 

 absorbed through the walls of the alimentary tract. 



THE CIRCULATORY SYSTEM 



The grasshopper has a long tubular heart (Fig. 214, E) lying along 

 the dorsal surface just beneath the body wall. From the heart there are 

 arteries and sinuses connecting the various parts of the body. Due to its 

 position the heart is often called the dorsal vessel. 



Anteriorly the heart is prolonged into a tube leading to the head and 

 is partially divided by valves into eight chambers. The position of the 

 heart-valves allows blood to flow headward only. 



