T^33LE OF CONTENTS. 



Page. 



Prefatory note by Dr. F. V. Haydon v 



Lotter to the geologist-in-charge 1 



List of authorities 3 



Pakt I. — The Acridid^s; op thk United States 7 



Introduction 9 



External structure and terminology 10 



luternal structure ii2 



Explanation of wood-cuts 27 



Classification .- 29 



Classification of North American genera 41 



Geographical distribution of the genera and species of North American xVcridida; 42 



Notes on some United States species 4C> 



Sj'noptical table of the United States genera 49 



Descriptions of the genera and species of the United States r)3 



Sub-Fam. I. — Acridiaai 5r> 



Divis. I. — Conocephalidcs 5G 



Sec. 1. — Microcerides 56 



Group 1. — Proseopini 56 



Sec. 2. — Macroceridos 5G 



Group 2. — Trjxaliul .''ifi 



Gen. Tryxalis 57 



Gen. Mesops 59 



Gen. Opomala 62 



Gen. Pyrgomorpha 6() 



Group 3. — Trigonopterygini 70 



Divis. II. — Orthocerides , 70 



Gronp 4. — ffidipodiui 70 



Section 1 72 



Gen. Oxycoryphus 72 



Gen. Chrysochraon 74 



Gen. Acroloiihitus 77 



Gen. Pedioscertetes 79 



Gen. Stenobothrus 80 



Gen. Gomphocerus 95 



Section II 97 



Gen. Stetheoi)hyma 98 



Gen. Tragocephala 100 



Gen. Tomonotus - 104 



Gen. Oedipoda 108 



Gen. Tropidolophus 138 



Gen. Stauronotus 139 



Gen. Boopedon 140 



Gen. Brachypepliis 142 



Group 5. — Acridini 143 



Gen. Peisotettix 145 



Gen. Platyphyma 154 



Gen. Ommatolamiiis - 156 



Gen. Caloi)tenU3 157 



Gen. Chromacris 167 



Gen. Acridium 168 



2780 1 



