TABLE OF CONTENTS 



PAGE 



Acknowledgments 9 



PART ONE. THE HOMOLOGY OF THE SETAE. 



I. Introduction 1 1 



Historical 12 



The Chaetotaxy of a Typical Segment 14 



II. Nature of the Evidence 14 



Definitions 15 



Difficulties IS 



Comparative Anatomy 17 



Ontogeny J 7 



Variation 20 



III. Application of the Evidence 20 



Application of Principles 21 



Choice of a Nomenclature 22 



IV. Setal arrangement in the Principal Superfamilies 23 



Suborder Jugatae 24 



First Instar 24 



Later Instars 25 



Conclusions from a Study of Jugatae 29 



Suborder Frenatae 29 



V. Primary and Subprimary Setae 3 2 



Alpha, 32; Beta, 32; Gamma, 33; Delta, 33; Epsilon, 33; Rho, 34; 

 Theta, 34 ; Kappa, 35 ; Eta, 35 ; Pi, 36 ; Mu, 37 ; Sigma, 38 ; Tau, 38. 



VI. General Conclusions 38 



Synonyms 39 



PART TWO. SYSTEMATIC OUTLINE OF FAMILIES AND GENERA 



Introduction 4 1 



Characters Used 42 



Head Parts, 43; Armature of the body, 44; Spiracles, 45; Prolegs, 45; 

 Other Structures, 47. 



