July 3, 1916 California Green Lace-wing Fly 519 



THE LARVA 



The larva when first hatched (fig. 3) is a delicate, white, nearly colorless 

 object, quite conspicuously hairy and with mandibles which are large in 

 comparison to the size of the body, these being about one-fourth its 

 entire length. Coquillett's (3) description follows : 



Mixed with a yellowish white and pinkish brown, the latter coior forming a dorsal 

 line and a series of lateral spots; along each side of the body is a row of yellowish 

 white tubercles; head yellowish white, marked with two diverging black stripes on 

 the top, and with a dusky streak each side, having in its middle a black dot; length, 

 7 mm. (A little over one-fourth of an inch.) 



LARVAL HABITS 



The hatching process requires but a few minutes, but the larva rests 

 on the empty eggshell for some time after emergence. When the eggshell 

 becomes dry and hardened, the larva hastily crawls down the supporting 

 egg stalk and eagerly begins searching for food. If 

 small aphids or thrips nymphs are present, it quickly 

 seizes one of these and begins feeding. If only full- 

 grown and large aphids are present, it is more cau- 

 tious, running in a circle around the tempting and 

 monstrous meal or following the aphid, ever and anon ,' 3 ' J. ry *°. . cai ~ 



a " ' . formca: First instar. 



stopping as if to consider whether or not it could 

 safely attack a creature so many times larger than itself. Finally, 

 however, its increasing hunger apparently overcomes all fear and it 

 pounces on its prey. The aphid is lifted bodily off its feet, the 

 lacewing larva all the time crushing, piercing, and sucking its prey. 

 The larvae of all lacewing flies extract their food from the host by 

 piercing it with their long, powerful mandibles, which are hollow, the 

 internal fluids of the host being rapidly absorbed through them. With 

 abundant food present the larva grows rapidly and quickly takes on a 

 robust appearance. 



LARVAL DEVELOPMENT 



The larvae in the course of their development molt twice, which divides 

 the larval period into three instars, with a total length of from 11 to 22 

 days, depending upon the prevailing temperature, the average length 

 being about 16 days. (See Table II.) During this period from 74 to 

 160 full-grown aphids were eaten by each larva, the number consumed 

 depending upon the temperature, the larvae being more active and 

 voracious during warmer weather. 



