26 



INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



pupate. In two weeks more the adults emerge. There are several 

 broods a year. The adults and eggs may be found during the winter 

 months in the southern pari of the Slate, but in the colder portions 

 only the eggs survive the winter. 



Nature of Work.— The larva? with their long sickle-like jaws extract 

 the juices of small soft-bodied insects. They are very ravenous and 

 consume quantities of both beneficial and destructive insects. 



Distribution.— The green lacewing occurs abundantly throughout 

 the entire State. 



Hosts.— The larvae prey on all soft-bodied insects, including plant 

 lice, mealy bugs, young scales, larva? of many beetles and on all of 

 our common mites. They are also cannibalistic. They prey largely 

 on insect pests, but often do great damage in destroying the larva? of 

 ladybird beetles. The pupal forms are preyed on by internal parasites, 

 \\ hich prevent large numbers from maturing. 



THE BROWN LACEWING 



Sympherobius august us Banks (Family Hemerobiidse) 

 (Fig. 23) 



Description.— The general appearance and shape are considerably 

 like the well-known green lacewing, but the wings are not so slender. 

 The ground color is brown with many darker blotches on the wings. 

 The larvae are dark gray or slate-colored with amber margins and, 

 when full-grown, are nearly f inch long. 



Life History. — The eggs are deposited among or near suitable prey 

 and hatch to slate-gray and tan-colored larva?, which are very active, 

 one very noticeable charac- 

 teristic being the constant 

 motion of the head when 

 they are searching for food. 

 When full-grown they are 

 nearly £ inch long. The 

 larva? spin thick white 

 cocoons in which to pupate. 

 This requires but a few days 

 or weeks, when the adults 

 emerue. 



Distribution.— The brown 

 lacewing occurs throughout 

 the central and southern 

 parts of the State. 



Hosts.— The larva? feed on many soft-bodied insects, including plant 

 lice and scales. It is a very efficient predator on the young of the 

 citrus mealy bug, Pseudococcus citri (Risso). 



Natural Enemies.— This insect would be far more useful if it were 

 not in turn preyed upon by a hymenopterous parasite (Isodromus 

 iceryce How.), which destroys the pupa? in the cocoons. In not a few 

 instances fifty to seventy-five per cent are parasitized. 



Fig. 23. — Larva and adult of the brown lace- 

 wing, Sympherobius angustus Banks. Enlarged 

 five times. (Author's illustration, P. C. Jr. 



Ent.) 



