Table of Contents xiii 

 CmVPTER IV 



PAGE 



The Paleontological Data Bearing on the Development and the 

 Specialization of the Wings of Insects 



(a) Earl}' views as to the paleontological evidence 85 



(6) On the origin of wings 87 



The paleontological date on the origin of wings 88 



(c) On the course of the evolution of each of the principal wing-veins 91 



The evolution of the costa 92 



The evolution of the subcosta 92 



The evolution of the radius 95 



The evolution of the media 99 



The evolution of the cubitus 1 04 



The evolution of the anal veins 1 07 



Summary 1 09 



CHAPTER V 

 The Development of the Wings of Insects 



(c) The development of the wings of nymphs no 



First appearance, position, and growth of the wings of nymphs no 



The tracheation of the wings of nymphs 113 



{b) The development of the wings of larvae and pupa; 114 



The development of the wdng-buds 114 



The development of the tracheation of the wings 115 



CHAPTER VI 



The Steps in the Specialization of Wings 118 



(a) The development of the wings 119 



{b) The basal connections of the tracheae that precede the wing-tracheae .... 119 



(c) The cross-veins 119 



(d) The longitudinal veins 120 



Table of the methods of specialization of the wings characteristic of the orders 



of insects 120 



List of orders 122 



CHAPTER VII 

 The Wings of the Orthoptera 



(a) The more general features of the wings of the Orthoptera 123 



{b) The wings of the Blattida; 123 



(c) The wings of the vSaltatorial Orthoptera i -7 



CHAPTER VIII 

 The Wings of the Isoptera 



(a) The more general features of the wings of the Isoptera 132 



{b) The tracheation and the venation of the wings of the Isoptera 135 



R^sum6 ... '43 



CHAPTER IX 

 The Wings of tiii-; Xkuroptera 



(a) The more general features of the wings of the Neuroptera 



{b) The special features of the wings of the Neuroptera 1 ' 



