CHAPTER XIII. 

 AlfALYTICAL TABLES, 



FOR DETERMINING THE FAMILIES OF INSECTS. 



How to Use tlie Tables. 



The purpose of the following tables is to enable a 

 student to find the family to which an insect belongs. 

 Their principal value is to direct the attention of the 

 student to the morphological differences that separate 

 families from each other. Morphological differences 

 are not of the greatest importance, and in some 

 instances may seem very trivial, but they enable us 

 to designate, easily and clearly, families that differ 

 widely from each other in habits, life history, and 

 economic importance. The study of type forms of 

 animals is not sufficient in itself to give us any idea 

 of the wealth of animal life that exists around us. 

 Particularly is this true of insects, with their 250,000 

 species already described. A very little time devoted 

 to the determination of insect families will add largely 

 to our appi'eciation of their importance. 



Although tables for six orders are given, it is not 

 expected that one class will try to master all of them. 

 It is better for one class or one student to confine 

 himself to the insects of one order until a satisfactory 

 familiarity with the insects of that order has been 

 acquired. 



In many instances it will be found very difficult 



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