294 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 6 



almost invariably confined to the fumigation districts. This condi- 

 tion, we are again led to believe, is brought about or encouraged by 

 the temporary absence of parasites. 



Such colonies of the soft scale are more often seen, perhaps, in young 

 orchards on newly broken ground, or even in older orchards where 

 ants are especially numerous. What was probably the worst infesta- 

 tion of the soft scale, that came to notice in the course of two years' 

 study, was located at Riverside, Cal., in the heart of a small tract 

 overrun by the Argentine ant (Iridomyrmex humilis Mayr). There 

 is not the least doubt that this and other species of ants eagerly attend 

 the soft scale for the sake of the honey-dew it copiously secretes, and 

 there is reason to believe that they unconsciously or even perhaps mili- 

 tantly protect their provider from the attack of parasites. So far as 

 we are aware, however, this conclusion has never been verified by 

 observation. 



The parasites of the soft scale observed in California during the past 

 two years are five in number, and being arranged in order of their 

 probable effectiveness stand as follows: Aphyciissp. nesirflavus Howard, 

 Microterys flavus (Howard), Coccophagus lecanii (Fitch), Coccophagus 

 lunulatus Howard, and Aphycus n. sp. near coquilletti Howard. 



The Microterys, and sometimes Aphycus also, is attacked by no 

 less than eight hyperparasites listed as follows: Coccophagus lecanii 

 (Fitch), Pachyneuron sp., Eusemion longipenne (Ashmead), Eusemion 

 n. sp., Perissopterus javensis Howard, Tomocera californica Howard, 

 Cheiloneurus n. sp., and Cerchysius sp. The relationship of still an- 

 other parasite, a new species of Anicetus, has not been determined, but 

 it is apparently hyperparasitic. 



Aphycus sp. near flavus (Howard) 



This Aphycus is a common and well-distributed parasite of the 

 soft scale in California, and also occasionally attacks small immature 

 specimens of the black scale {Saissetia olew Bern.).^ It has been given 

 first place in order of effectiveness because of its more general distri- 

 bution and its habit of destroying its host in the early stages before 

 any damage has been done or any offspring produced. As a parasite 

 of Coccus hesperidum it is partial to the young scales from 1 to 1.5 mm. 

 long, but will attack successfully much larger hosts as long as they are 

 still immature. Old scales that attain a certain degree of convexity 

 are free from further molestation. The smaller hosts are able to sup- 

 port only one parasite, but in the larger ones as many as six or even 



2 The original host record of .-1. flavus given by Howard is undoubtedly incorrect. 

 The pecuhar and speciahzed larval habits preclude the possibility of its being a 

 parasite of Lepidosaphcs beckii (Newm.) or any other Diaspine scale. 



