xx PANORPIDAE HEMEROBIIDAE 453 



Boreus and Bittacus were also observed by Brauer ; they are 

 essentially similar to those of Panorpa, but the larva in Boreus is 

 not provided with abdominal prolegs. The Panorpidae have 

 been separated from the other Neuroptera by certain naturalists 

 as a distinct Order, called Panorpatae by Brauer, Mecaptera by 

 Packard; but in their structure as well as in their metamorphoses 

 they are not so distinct from the Phryganeidae and the Hemero- 

 biidae as to justify this step. 



Fossil forms of Bittacus and of Panorpa have been found in 

 amber and in the Tertiary strata, and Scudder has described some 

 forms from Florissant in which there are no cross- vein lets in the 

 wings. Some remains from the English Lias have been referred 

 to Panorpidae by Westwood under the name Ortliophlebia, but it 

 is by no means certain that they really belong to the family. 



Fam. X. Hemerobiidae Ant-lions, Lacewing-flies, etc. 



Head vertical ; maxillae free, with Jive-jointed palpi ; labial palpi 

 three-jointed. Wings subequal in size, with much reticula- 

 tion, without anal area. Tarsi jive-jointed. Metamorphosis 

 great ; the larvae with mandibles and maxillae coadapted to 

 form spear-like organs that are suctorial in function. Pupa > 

 similar in general form to the imago, enclosed in a cocoon. 



FIG. 298. Drepanepteryx phalaenvides. Scotland. 



The Hemerobiidae are an extremely varied assemblage of 

 Neuroptera ; the perfect Insects of the various sub-families are 

 very different in appearance, but the family as a whole is 

 naturally defined by the very peculiar structure of the mouth- 

 organs of the larvae. These Insects have, in fact, a suctorial 



