CHAPTER 15 

 THE LOCUST 



A survey of the several classes of the great Phylum Arthropoda 

 was given at the close of the preceding chapter. The Insecta, or 

 Hexapoda, are the most important class of land-dwelling arthro- 

 pods. Their numbers, both in species and in individuals, far 

 exceed those of all other terrestrial animals. While the grass- 

 hoppers and their allies are not the simplest type among the 

 Hexapoda, they represent a more generalized condition than is 

 found in such forms as the moths and butterflies, the bees and 

 wasps, or the two-winged flies. They are, moreover, familiar 

 animals, of large size as compared with the majority of insects; 

 their mode of development is relatively simple; and their habits 

 and life histories have been extensively studied because of their 

 economic importance. Like the earthworm and the crayfish, 

 the grasshopper is, therefore, representative of the class of animals 

 to which it belongs, and illustrates the biological principles that 

 are exemplified by that class. 



The words "grasshopper" and "locust" are used indiscrim- 

 inately in popular speech, as when one reads of locusts in the Bible 

 or of the " grasshopper years " in the early days of Kansas. If any 

 scientific distinction is to be made between the two terms, it is 

 that the locusts are the " short-horned " grasshoppers, or those in 

 which the antennae are relatively much shorter than in the "long- 

 horned" forms which have long and delicate antennae. The 

 roadside locusts are examples of the former type, and the meadow 

 grasshoppers and katydids, with antennae even longer than the 

 body, are examples of the latter. Unfortunately, the name locust 

 has also been apphed in the United States to an entirely different 

 type of insect, the periodical cicada, which is popularly called 

 the thirteen-year or seventeen-year "locust." As there are 

 many species among the locusts that may be used for the present 

 study, the account that follows has not been confined to a single 



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