ENTOMOLOGY IN OUTLINE NEUROPTERA. 61 



in splitting it up into several minor orders, some of which are repre- 

 sented by a single family. Some authorities divide it into two sub- 

 orders, the true Neuroptera and the Pseudo-neuroptera. In the former 

 the metamorphosis is complete, and in the latter it is incomplete. In 

 this classification of Neuroptera and Pseudo-neuroptera, the insects 

 with incomplete metamorphosis are separated into Ephemeroptera, or 

 mayflies; Odonata, or dragon-flies; Plectoptera, or stone-flies; Platyptera, 

 the white ants, book-lice, and bird-lice. Comstock, however, erects 

 separate orders for these, and does not recognize the Pseudo-neuroptera. 

 As few of these are of great economic importance, and as this is not a 

 scientific treatise, we give the minor orders place under the general title 

 of Neuroptera. 



Order Meeoptera includes but one family, the scorpion-flies, so-called 

 because the last abdominal segment has a strong resemblance to the 

 sting of the scorpion. It is not a sting, however, and contains only a 

 set of grasping organs. These insects are of no economic importance. 



Order Triehoptera, the caddice flies, in their larval stage, are found 

 in streams and have the peculiarity of constructing for themselves 

 shelters of particles of wood, gravel, and other substances. The larvse 

 remain in these structures, the head alone protruding, and are thus safe 

 from outside foes. The material of which these structures are joined 

 together is a silk spun by the worm, and the inside of the tubes is 

 generally lined with the same substance. Another peculiarity of these 

 insects is that under water they construct a web very similar to that of 

 the spider on the surface. 



Order Ephemerida includes the mayflies, which are very delicate 

 insects that appear in enormous numbers on summer evenings on the 

 margins of quiet streams and lakes. The mayfly is an aquatic insect, 

 and spends its entire larval life in the water. In its perfect form it is 

 a beautiful sprite-like insect, without mouth parts, its only object in 

 life being to lay the eggs which are to produce a new generation. This 

 is accomplished in a few hours and the insect passes away. They have 

 no economic value. The metamorphosis is incomplete. 



Order Odonata (Dragon-flies). Members of this order are easily 

 recognized and are well known. They are, in their larval form, 

 aquatic, and have an incomplete metamorphosis. They may be classed 

 as beneficial, as they live almost wholly on mosquitoes in both their 

 larval and mature stages, and are probably one of nature's most effect- 

 ive methods of keeping down these troublesome pests. Unfortunately, 

 this insect has been credited with malign powers, and ignorant people 

 regard it as a dangerous insect. It is at once one of the most graceful. 



