PREFACE 



IN preparing this book the author had in mind the wants both of 

 the student and the teacher. For the student's use the more diffi- 

 cult portions, particularly that on the embryology, may be omitted. 

 The work has grown in part out of the writer's experience in class 

 work. 



In instructing small classes in the anatomy and metamorphoses 

 of insects, it was strongly felt that the mere dissection and drawing 

 of a few types, comprising some of our common insects, were by no 

 means sufficient for broad, thorough work. Plainly enough the 

 laboratory work is all important, being rigidly disciplinary in its 

 methods, and affording the foundation for any farther work. But 

 to this should be added frequent explanations or formal lectures, 

 and the student should be required to do collateral reading in some 

 general work on structural and developmental entomology. With 

 this aim in view, the present work has been prepared. 



It might be said in explanation of the plan of this book, that the 

 students having previously taken a lecture course in the zoology of 

 the invertebrates, were first instructed in the facts and conclusions 

 bearing on the relations of insects to other Arthropoda, and more 

 especially the anatomy of Peripatus, of the Myriopoda, and of Scolo- 

 pendrella. Then the structure of Campodea, Machilis, and Lepisma 

 was described, after which a few types of winged insects, beginning 

 with the locust and ending with the bee, were drawn and dissected ; 

 the nymph of the locust, and the larva and pupa of a moth and of 

 a wasp and bee being drawn and examined. Had time permitted, 

 an outline of the embryology and of the internal changes in flies 

 during their metamorphoses would have been added. 



