CONTENTS 



PAGE 



Introduction ...... By the Editor ix 



Description of Plates ........ xli 



Alternating Generatio.ns in Oak Gall-Flies. By Dr. Adler i 



Chapter I. Early Observations and Methods of 



Research ....... i 



II. Descriptions of Cynipidae Observed. Table 



of Alternating Generations ... 9 



III. On Gall Formation ..... 97 



IV. The Ovipositor and the Egg . . iio 

 V. Grouping of the Cynipidae . . .129 



VI. Alternating Generation, and Cyclical 



Propagation • . . . . - 149 

 Pediaspis aceris and Bathyaspis .\ceris . . . 159 



Cynips Kollari ...... By the Editor 163 



Synoptical Table of Galls .... ,, 168 



Classification of the Cynipidae ... ,, 172 



Bibliography ....... ,, 182 



Index . . . . . . . . . . . .191 



1 ^ - 



