Vol. XXV. August, /p/j. No. 3 



BIOLOGICAL BULLETIN 



LOCAL DISTRIBUTION OF GRASSHOPPERS IN 

 RELATION TO PLANT ASSOCIATIONS. 



ARTHUR G. VESTAL. 

 CONTENTS. 



I. Introduction 141 



Physiography of the Region 142 



General Character of the Vegetation 143 



II. The. Plant Associations and the Grasshoppers which Occur Within Them 143 



Associations of the Northeastern Conifer Province 144 



Associations of the Eastern Deciduous Forest Province 145 



Local Associations 147 



Ruderal Associations 148 



Arrangement of the Associations as Habitats 150 



III. Summary of Habitat-Distribution of the Species 152 



IV. General Discussion 155 



The Assignment of Terrestrial Animals to Habitats 155 



Estimation of Relative Numbers in Different Habitats 164 



The Relation of the Animal to Plant and Animal Communities 166 



Successional Relations 169 



Geographic Relations 1 73 



Seasonal Relations 1 75 



V. Summary 177 



VI. Acknowledgments and Bibliography 178 



I. INTRODUCTION. 



During the summer of 1912, while at the biological station of 

 the University of Michigan, at Douglas Lake, the writer found 

 opportunity to study the relation between local distribution of 

 grasshoppers and the plant associations. The group studied 

 includes the three subfamilies Tryxalince, (Edipodince, and 

 Acridiince, of the orthopteran family AcridiidcB. 



Habitat-distribution of Orthoptera has received considerable 

 attention. Published accounts of Orthoptera contain the bulk 

 of the data on habitats. The studies of Morse ('04), and of 



141 



