INTRODUCTION 



PURPOSE AND SCOPE OF THE PAPER 



The systematic literature dealing with certain groups of the Coccidae 

 or scale insects is extremely unsatisfactory, this condition being especially 

 pronounced in the case of those groups commonly called the "soft scales." 

 The present author (4)f has stated in an earlier paper that ". . . of the 

 nearly 100 species of mealy bugs thus far described from North America, 

 including some 35 from California, not more than three or four are 

 recognizable at all on the basis of the published descriptions if taken apart 

 from their typical host and their type locality," nor at the time of the 

 present writing does this statement need any extensive modification. A 

 few species have been described since the statement was originally made 

 and to some of these it may not apply, but so far as the species known 

 at that time are concerned, the additional claim may safely be made that 

 even under the optimum conditions cited, the identification of many of 

 our species can not be accomplished with reasonable certainty. 



The actuating motive of the present paper has been the hope of 

 remedying this condition as far as may be for those species of mealy 

 bugs occurring in California. However, progress toward this goal has 

 been made possible only by the utilization of certain methods not ordi- 

 narily employed, at least by American entomologists, and by the empha- 

 sizing of certain morphological features of which some have been en- 

 tirely overlooked and of which the full significance of none seems at any 

 time to have been realized. The scope of the paper has therefore been 

 extended to include an explanation of these methods and a description 

 of these morphological features. 



The restriction of the paper to those species occurring in California 

 has not been due to any desire to keep within the boundaries of some 

 artificially defined political unit nor to any belief that the California 

 mealy-bug fauna is at all separable as a group from that of the rest of 

 North America. The limitations imposed have been purely those of can- 

 venience. It so happens that most of the species known from west of 

 Colorado and New Mexico have been described from California and that 

 the types of these are for the most part in western collections. It also 

 happens that most of the California species have been taken from two 



fNumbers in the text refer to the list of references cited at the end of the 

 paper. 



