THE INSECy WORLD. 



75 



grove ot eggs on stilts. This is supposed to insure their safety 

 from wandering predaceous forms that might otherwise feed upon 

 them. When the larva hatches it climbs down the slender 

 thread, and attacks and feeds upon the first suitable s])ecimen it 

 can find, — usually a young plant-louse. Now, here is another 

 peculiarity : it does not chew or tear its prey, but holds it firmly, 

 sucking the juices by means of grooves on the inner side of the 

 large mandibles, which are closed by the slender maxillai. The 

 larva grows rapidly, becoming rather more than a quarter of an 

 inch in length, narrow, spindle-shaped, pointed at the anal ex- 

 tremity, the head distinct and with prominent sickle-shaped 

 mandibles. When full-grown it spins, by means of anal glands, 

 a perfectly spherical, white, silken cocoon of very dense texture, 

 and small in proportion to the larva. It resembles a moderate 

 sized pearl in form and appearance, and when the adult is ready 

 to emerge, a circular lid is lifted off to give the matured pupa 

 exit. Comparing the fully developed insect with the cocoon 

 from which it issued, the marvel is great that it was ever packed 

 away in so small a space. 



These insects are really of much practical value, frequenting, 

 as many of them do, tilled fields and orchards, feeding upon 

 larvae, plant-lice, and similar creatures. They become injurious, 

 however, in some parts of California, where they attack and 

 destroy coccinellid or lady-bird larvae. 



Somewhat closely allied in all stages to the Hemerobiidce are 

 the Myrme/eonidce, or "ant-lions," but they are larger, with 

 longer and narrower wings, and clubbed antennae. As before, 

 the adults are graceful, harmless creatures, which fly mostly at 

 night, while the larvae are predatory, resembling the "aphis- 

 lions" in structure, save that they are broader and chunkier in 

 appearance. They are also peculiar in that many of them 

 capture their prey in pits or traps. 



In constructing its trap, the larva usually selects a spot of mod- 

 erately compact, fine sand, and excavates a funnel-shaped pit 

 with the sides as steep as the sand will lie. It remains buried 

 and invisible in a little gallery at one side of the bottom, in wait 

 for any unlucky creature that may come within reach. Ants are 

 the most frequent victims, from their wandering habits and their 

 tendency to investigate, a pause at the brink resulting in a slip of 



