vi INTRODUCTION 



insects whose entire life histories cannot be studied with- 

 out continuation of the observations throughout the year. 



This work aims to present the subject in a simple 

 fashion so that the student of the secondary schools can 

 use all that is given. It attempts to make the student 

 acquainted with only the more important groups and does 

 not go as deeply into the scientific phases of classification 

 and structure as a work intended for more advanced stu- 

 dents should. 



Neither does it give as much attention to details of 

 description of species as a work of larger scope could. 

 The aim is rather to present the general idea of the sub- 

 ject so that it can be covered in the time that the schools 

 may reasonably be expected to allot to it. Brevity is 

 secured rather by omission than by any lack of accuracy 

 in the statements included. The classification employed 

 is the one in general use and the one best known to the 

 greater number of entomological students who will be 

 likely to use the work for a text. Its greater simplicity 

 warrants its use rather than the more scientific arrange- 

 ments and nomenclatures employed by the most modern 

 writers. 



The chapters on economic entomology are presented 

 with the same object: to give as concise an idea of the 

 more common injurious forms as is possible in a limited 

 space. Here again, brevity is secured by the omission of 

 the less important and less generally distributed species 

 rather than by slighting those that are considered. 



The junior author is responsible for the preparation of 

 Part I, and the senior author for Part II. 



E. D. S. 



L. M. P. 

 June, 1916. 



