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Pomona College Journal of Entomology 



icola Kocli., wliicli it .sctins to ])rcfVr to all otlu-r apliids. There arc millions of the 

 eggs, larvae, pupae and adults to be found in every walnut orchard in Ventura 

 County and large numbers are found in the citrus orchards in the early spring 

 before tile walnuts begin to leaf out. It is by far the most important beneficial 

 insect of the three herein described. 



Scymus sordidus Horn. 

 (Figures 198 I) and '■20-2) 



This is one of the smallest of the aphid feeders, but very common in localities 

 near the foothills, where it feeds especially upon Aphis gossypii Glover. 



The larva is considerably larger than the adult, being nearly a quarter of an 

 inch long atid half as wide. It is easily recognized by its heavj' coating of rather 

 long, wliite, cottony wax and is often mistaken by citrus growers for a mealy bug. 



Figure 202. Larva of Scymnus sordidus 



The adult is scarcely more than one-eighth of an inch long and two-thirds as 

 wide, light brown to very dark brown in color, and with elongated body. It is 

 technically described by Thos. Ca.sey (See P. C. Jr. Ent. Vol. Ill, No. 3, p. 520, 

 Sept. 1911) briefly as follows: "Body elongate oval. Length 1.65 mm., width 0.9 

 mm. Pronotum piceous, minutely, not very closely, punctulate, the sides not quite 

 eontinunus. Elytra pale, with margins nubilously blackish, more broadly at base, 

 finely ;ind rather closely punctate. Abdominal lines extending outward externally 

 parallel to the edge of the segment and a slight distance therefrom, prosternum 

 relatively slightly wider between coxae, flat and wholly devoid of carniae; genital 

 or 'sixth' ventral segment, usually developed." 



This insect is a native of California and especially abundant in the southern 

 citrus counties, where it also does good work on the citrus mealy bug. 



