A GRASSHOPPER 



INSECTA 



AN ORTHOPTEROUS INSECT. A LARGE GRASSHOPPER 



Observe the shape, color, and external anatomy of the animal. 

 Note the long, vermiform body and the large head. The body, 

 as in all insects, is made up of a number of serially arranged 

 segments, called somites or metameres, which fall into two divi- 

 sions — the thorax and the abdomen. The head is unsegmented, 

 being composed of a number of completely fused somites, and 

 bears upon its dorsal and anterior surface a pair of long, jointed 

 feelers or antennae, which are important sense-organs, a pair of 

 large compound eyes, and three small, dot-like eyes, called ocelli, 

 which it may be necessary to look for with a hand lens ; on its 

 ventral side are the mouth-parts, the organs with which it tastes, 

 grasps, and masticates its food. Examine these mouth-parts 

 with a hand lens. Observe the long, broad upper lip and pass a 

 needle under its ventral edge. Back of the upper lip will be 

 seen the strong mandibles, and by pressing these to the right and 

 left the two remaining pairs of mouth-parts, the maxillae and 

 the under lip, will be seen. Note the two pairs of jointed palps 

 belonging to them, which are probably organs of taste. These 

 parts will all be studied later in detail. 



The thorax is made up of three somites, which are called the 

 pro-, meso-, and metathorax. Notice that the thorax is not sepa- 

 rated from the abdomen by a constriction, as it is in the wasp, 

 but, however, that it may be easily distinguished from the 

 abdomen by its greater diameter. The prothorax is movable, 

 as in the beetle, and its dorsal and lateral surfaces are covered 

 by a large shield. On the ventral side of the prothorax, 

 between the prothoracic legs, is, in many grasshoppers, a short 



