ORDER V. NET-WINGED INSECTS. 215 



mained unanswered longer than it should have been, and I 

 now improve a leisure hour to fulfill this duty. 



" Just now, at Professor Agassiz's request, I have been 

 revising the Neuroptera, and have become much interested 

 therein. Some of the German naturalists (Erichson, etc., 

 etc.) have undertaken to break up this order, leaving there- 

 in only those genera which undergo a complete transforma- 

 tion, and have inactive pupae, such as Semblis, Corydalis, 

 Chaulisdes, Raphidia, Mantispa, Ilemerobius, Myrmeleon, As- 

 calaphus, Bittacus, Panorpa, and Phryganea ; and they trans- 

 fer Psocus, Tennes, Ephemera, Libellula, Perla, etc., to Or- 

 thoptera, or put them among the Blatta, Mantes, Spectra, 

 and Grylli! 



" Linnaeus evidently regarded Libellula as the type of his 

 order Neuroptera, and this genus seems to have nothing in 

 common with the Orthoptera save a remote resemblance in 

 the structure of the labium and labial palpi, and the im- 

 perfect transformation. This transformation, also, is not 

 analogous to that of Orthoptera, excepting only in the fact 

 that the pupse are active and take food ; in other respects 

 they are entirely unlike the perfect insects, whereas the 

 pupoe of the Orthoptera closely resemble the perfect insect, 

 with the exception only of wanting fully-developed wings. 

 Hence I maintain that the Libellulada3 can not with any 

 propriety be put among Orthopterous insects. 



" Libellula is closely connected in organization and hab- 

 its with other Neuroptera, and hence, if it be retained in 

 this latter order, Ephemera, Perla, Terrnes, etc., must remain 

 also. My knowledge of these insects, in their various states, 

 is probably equal to that of the Berlin entomologists, and 

 therefore I feel authorized to put my own judgment and ex- 

 perience on the subject against theirs. Without going very 

 deeply into particulars, allow me to contrast the characters 

 of Orthoptera and Neuroptera, thus : 



" ORTHOPTERA. None of them aquatic. All of them 

 active, taking food and growing in the pupa state, which 

 resembles the winged or adult state, except in wanting fully- 

 grown wings. The parts of the mouth well developed ; the 

 labial palpi never wanting ; the head more or less immersed 

 at the base in the pro-thorax, and possessing only a limited 

 power of motion ; antennae always much longer than the 

 head, often VCM-V long, mostly setaceous or filiform, very 



