INTRODUCTION 



The Scale insects of this State have received a great 

 deal of attention particularly along economic lines. This is 

 the first attempt at making a synopsis for the recognition 

 of our species. The form of the synopsis and of the refer- 

 ences is uniform with the author's Key to Orthoptera, in 

 which full explanations will be found. 



The study of these insects requires ability to use the 

 compound microscope and considerable microscopic tech- 

 nique. A laboratory guide for the study of scale insects 

 is being prepared for publication for the use of those who 

 may wish to take up the subject by themselves and desire 

 a detailed description of the study methods. 



The most useful books on scale insects are Newstead's 

 Monograph of the British Coccidae, which contains the 

 fullest general account of these insects, and Fernald's 

 Catalogue of the Coccidae of the World, which is the best 

 guide to the literature. For references to the literature of 

 the local fauna, the present work will be found useful. 



The author hopes that this key will stimulate many ento- 

 mologists on this coast to collect and study in this group. 



C. W. WOOUWORTH. 



University of California, October, 1903. 



