THE OLIVE INSECTS OF CALIFORNIA 49 



Among the parasitic insects, are the scutellista, Scutellista cyanea 

 Mots., also known as the African fly, Dilophogaster calif ornicus 

 (How.), Aphycus sp. and the lecanium parasite, Coccophagus lecanii 

 (Fitch). Of these the scutellista is by far the most important and 

 at times becomes remarkably numerous, infesting nearly every egg- 

 laying female of the scale. The larvae feed upon the eggs, but usually 



Fig. 4. The ivy or oleander scale, Aspldiotus hederae (Vail.). Adult females 

 and young on an olive. (Original.) 



leave enough to insure little or no diminution in the number of scales 

 for the next year. Though not at all dependable, it is often relied 

 upon by growers to do what can be accomplished with certainty with 

 sprays, with the result that considerable loss is caused by the omission 

 of control measures every year. The other parasites listed work 

 much more spasmodically and little real investigation has ever been 

 done to ascertain whether they do any good or not. 



