A GRASSHOPPER (Melanoplus differ entialis). 



Phylum X, ARTHROPODA; class 4, INSECTA; order 2, ORTHOPTERA. 



HABITAT. Grasshoppers are probably common wherever grass or 

 herbaceous vegetation grows, for genera and species are usually 

 numerous in any locality inhabited by man. To the groups having 

 short antennae the term Locust is also frequently applied. Grass- 

 hoppers feed on green vegetation of almost any sort, especially such as 

 grows low on the ground. Most of the adults die in the fall, in tem- 

 perate climates, the females leaving a packet of eggs to perpetuate 

 the species. They are very destructive to growing crops, especially 

 when rapid increase of numbers and consequent scarcity of food forces 

 them to migrate in swarms from their native haunts. 



Technical Note. Live grasshoppers can be kept under bell jars or in 

 cages consisting of a lamp or lantern chimney tied over at the top 

 with gauze and standing upright on the earth in a common flower pot. 

 They should be supplied with fresh grass at least once a day. Pre- 

 served material, kept in two per cent formalin or seventy per cent 

 alcohol, may be used when fresh specimens can not be obtained from 

 the field. 



EXTERNAL STRUCTURE. With grasshopper and lens in hand note 

 the following relations and parts: 



a) The head, at the anterior end of the body. Is it placed in line with 



the longer axis, or at right angles to it ? 



b) The thorax, movably articulated with the head, but immovably 



fused with the first segment of the posterior body region. There 

 are three divisions of the thorax, each bearing a pair of legs. 

 They are termed, respectively, the pro-, meso-, and metathorax, 

 beginning with the most anterior division. Which of these is 

 free to move at either end ? Trace out the line of division between 

 the other two. 



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