AKTHEOPODA. 117 



The Planipennia alone constitute the Neuroptera according to 

 the views of some authors, the remainder, including Trichoptera, 

 being placed with the Orthoptera, under the name of " Pseudo- 

 Neuroptera " (Archiptera of Hackel). 



According to Packard, Libellulidae and the Ephemerida? are 

 the most typical of the Neuroptera. These families and the Per- 

 lidas are among the earliest known insects. They seem to occur 

 most abundantly in the Devonian formations of North America. 



To this order belong the destructive white ants, Termes belli- 

 cosus and other species ; the death-watch, Apropos pulsatoria ; 

 the may-fly, Ephemera milgata ; and ant-lion, Myrmeleon formi- 

 caleo. Libellulidse are known generally as dragonflies or horse- 

 stingers, and in the United States as the " Devil's darning- 

 needles." It is curious to contrast these names with that of the 

 French, "Demoiselles." Chrysopa, of which there are many 

 species, is known as the " Golden-eye." 



The earlier stages of these insects are very variable. In the 

 Libellulida?, Termitidae, and Ephemeridaa, although very unlike 

 each other, the metamorphosis is sernicomplete, while Chloeon 

 undergoes a series of not less than twenty moultings, in some 

 stages a retrograde movement taking place. Prof. Westwood, 

 with regard to the earlier states of the order, proposes two pri- 

 mary divisions: " 1. Those with an active pupa, undergoing a 

 metamorphosis which, for want of a better name, we may, with 

 MacLeay, term sub-semicomplete ; in all which there is a greater 

 dissimilarity between the larva and imago states than exists in 

 the insects typical of the monomorphous, semicomplete metamor- 

 phosis. Here belong the Psocidae and Termitidae, which have 

 terrestrial lar\93, and the Libellulidae, Ephemeridae, and Perlidae, 

 which are aquatic in their preparatory states. I term the species 

 of this division Biomorphotic insects. 2. Those which have 

 quiescent incomplete pupae, which, however, acquire the power 

 of locomotion shortly before the assumption of the perfect state. 

 This division (Subnecromorphotica) comprises the families Myr- 

 meleonidae, Hernerobiidoe, Sialidae, Panorpidae, Baphidiidas, and 

 Mantispidae." The aquatic larvae breathe by means of filamen- 

 tous branchias. 



Retaining, with M'Lachlan, the order Neuroptera " as a 

 matter of convenience only," it may be naturally divided into 

 seven suborders : 



Wings naked, rarely a few hairs or scales. 



\V ings folded in repose PLECOPTERA. 



