582 NEUROPTERA. 



canals are short, and always have on their lower extremity two 

 long or ovoid accessory follicles." (Siebold.) 



The classification of the Neuroptera is difficult from the 

 lowness of the type, which presents an unusual number of deg- 

 radational forms, such as are indicated bej^ond, and because 

 the different families vary so much among themseh'es, and 

 contain forms which mimic the higher groups of insects. 

 Though the type is the lowest among hexapodous insects, yet 

 there constantly recur characters which are found onl}^ in the 

 highest insects. For example the PJiryganeidce are Neu- 

 ropterous throughout, 3'et there are many of the less impor- 

 tant characters which ally them most intimately with the 

 Lepidoptera, especially the Tine idee. 



However all Neuroptera agree in the lax composition of 

 the body, inducing a w^orm-like, elongated form. The meta- 

 morphoses are, in the more typical families, less complete than 

 in other insects, except the Hemiptera and Orthoptera, and 

 upon the whole the organs of vegetative life are largely devel- 

 oped over those of animal life, making them generally very 

 sluggish in their motions (though the adult Libellulidse are an 

 exception), and inducing an abnormal size of the bod}^, as this 

 suborder contains many of the largest and most monstrous of 

 insects. The researches of Professor Dana and Messrs. Hartt 

 and Scudder show that the Neuroptera shared with the Orthop- 

 tera the possession of the low marshy lands of Devonian and 

 Carboniferous times, and the forms discovered in the rocks of 

 those periods indicate that they were often of gigantic propor- 

 tions, and among the most degraded of their type. 



Dr. Anton Dohrn has described, under the name of Euge- 

 reon Bockingi (Fig. 572), perhaps the most remarkable fossil 

 insect yet discovered. It occurred in the Permian formation 

 in Germany. He considered it as combining Hemipterous and 

 Neuropterous characters, though more closely allied to the 

 Neuroptera. Dr. Hagen writes me that "Eugereon belongs to 

 Dictyoneura Goldenberg, and is perhaps identical with one of 

 the species described and figured by Goldenberg." Dictyo- 

 neura is said by Goldenberg to resemble the Neuropterous 

 genus Semblis. Dr. Hagen also informs me that Gerstaecker, 

 after an examination of Booking's specimen, ''thinks Eugereon 



