74 A BOOK OF INSECTS 



Order XL — Anoplura. 



Little need be said of these insects. By many autho- 

 rities they are regarded as Heteroptera, which have become 

 simplified as a result of their parasitic habits. They are 

 all small and wingless, while the mouth-parts are modified 

 to form a fleshy suctorial beak, which is provided with a 

 circle of booklets near the base. They spend their whole 

 lives upon the bodies of mammals, whose blood they 

 suck. Only one family is recognised, viz. the PedicuUdce. 



Order XII. — Neuroptera. 



In its restricted form, the order Neuroptera includes 

 the alder-flies, ant-lions, lace-wings and their allies. All 

 these insects possess biting mouth-parts, and (with few 

 exceptions) four nearly similar wings with a complex net 

 veining. They undergo a complete metamorphosis, a 

 quiescent pupa state always preceding the appearance of 

 the imago. Most of the species prey upon other insects. 

 Their larvae are of the campodeiform type. Their man- 

 dibles are usually grooved on the inner edges, and through 

 these grooves the juices of the prey are drawn into the 

 gullet. Thus, while the larva? are typically mandibulate 

 insects, they may nevertheless be said to feed by suction. 

 The order Neuroptera comprises nine families. 



Alder-flies (Sialidce) lay their eggs in rows on grass 

 stems, usually on the banks of rivers or streams. When 

 the larva? hatch, they enter the water, where they prey 

 upon small aquatic creatures. When full-grown, they 

 leave the water, and burrow in the earth, where they 

 change to pupa?. There are several British species — the 

 common alder-fly, which figures on the angler's list, being 

 Stalls lutaria. The genus Corydalis, which is represented 



